CASA fork: initial commit

Snapshot from http://cse.unl.edu/~citportal/.

12 files changed, 2173 insertions, 0 deletions

diff --git a/minisat/LICENSE b/minisat/LICENSE
new file mode 100644
index 0000000..c87a327
--- /dev/null
+++ b/minisat/LICENSE
@@ -0,0 +1,20 @@
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the
+"Software"), to deal in the Software without restriction, including
+without limitation the rights to use, copy, modify, merge, publish,
+distribute, sublicense, and/or sell copies of the Software, and to
+permit persons to whom the Software is furnished to do so, subject to
+the following conditions:
+
+The above copyright notice and this permission notice shall be included
+in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/minisat/include/Alg.h b/minisat/include/Alg.h
new file mode 100644
index 0000000..240962d
--- /dev/null
+++ b/minisat/include/Alg.h
@@ -0,0 +1,57 @@
+/*******************************************************************************************[Alg.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Alg_h
+#define Alg_h
+
+//=================================================================================================
+// Useful functions on vectors
+
+
+#if 1
+template<class V, class T>
+static inline void remove(V& ts, const T& t)
+{
+    int j = 0;
+    for (; j < ts.size() && ts[j] != t; j++);
+    assert(j < ts.size());
+    for (; j < ts.size()-1; j++) ts[j] = ts[j+1];
+    ts.pop();
+}
+#else
+template<class V, class T>
+static inline void remove(V& ts, const T& t)
+{
+    int j = 0;
+    for (; j < ts.size() && ts[j] != t; j++);
+    assert(j < ts.size());
+    ts[j] = ts.last();
+    ts.pop();
+}
+#endif
+
+template<class V, class T>
+static inline bool find(V& ts, const T& t)
+{
+    int j = 0;
+    for (; j < ts.size() && ts[j] != t; j++);
+    return j < ts.size();
+}
+
+#endif
diff --git a/minisat/include/BasicHeap.h b/minisat/include/BasicHeap.h
new file mode 100644
index 0000000..556d98f
--- /dev/null
+++ b/minisat/include/BasicHeap.h
@@ -0,0 +1,98 @@
+/******************************************************************************************[Heap.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef BasicHeap_h
+#define BasicHeap_h
+
+#include "Vec.h"
+
+//=================================================================================================
+// A heap implementation with support for decrease/increase key.
+
+
+template<class Comp>
+class BasicHeap {
+    Comp     lt;
+    vec<int> heap;     // heap of ints
+
+    // Index "traversal" functions
+    static inline int left  (int i) { return i*2+1; }
+    static inline int right (int i) { return (i+1)*2; }
+    static inline int parent(int i) { return (i-1) >> 1; }
+
+    inline void percolateUp(int i)
+    {
+        int x = heap[i];
+        while (i != 0 && lt(x, heap[parent(i)])){
+            heap[i]          = heap[parent(i)];
+            i                = parent(i);
+        }
+        heap   [i] = x;
+    }
+
+
+    inline void percolateDown(int i)
+    {
+        int x = heap[i];
+        while (left(i) < heap.size()){
+            int child = right(i) < heap.size() && lt(heap[right(i)], heap[left(i)]) ? right(i) : left(i);
+            if (!lt(heap[child], x)) break;
+            heap[i]          = heap[child];
+            i                = child;
+        }
+        heap[i] = x;
+    }
+
+
+    bool heapProperty(int i) {
+        return i >= heap.size()
+            || ((i == 0 || !lt(heap[i], heap[parent(i)])) && heapProperty(left(i)) && heapProperty(right(i))); }
+
+
+  public:
+    BasicHeap(const C& c) : comp(c) { }
+
+    int  size      ()                     const { return heap.size(); }
+    bool empty     ()                     const { return heap.size() == 0; }
+    int  operator[](int index)            const { return heap[index+1]; }
+    void clear     (bool dealloc = false)       { heap.clear(dealloc); }
+    void insert    (int n)                      { heap.push(n); percolateUp(heap.size()-1); }
+
+
+    int  removeMin() {
+        int r   = heap[0];
+        heap[0] = heap.last();
+        heap.pop();
+        if (heap.size() > 1) percolateDown(0);
+        return r; 
+    }
+
+
+    // DEBUG: consistency checking
+    bool heapProperty() {
+        return heapProperty(1); }
+
+
+    // COMPAT: should be removed
+    int  getmin    ()      { return removeMin(); }
+};
+
+
+//=================================================================================================
+#endif
diff --git a/minisat/include/BoxedVec.h b/minisat/include/BoxedVec.h
new file mode 100644
index 0000000..bddf410
--- /dev/null
+++ b/minisat/include/BoxedVec.h
@@ -0,0 +1,147 @@
+/*******************************************************************************************[Vec.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef BoxedVec_h
+#define BoxedVec_h
+
+#include <cstdlib>
+#include <cassert>
+#include <new>
+
+//=================================================================================================
+// Automatically resizable arrays
+//
+// NOTE! Don't use this vector on datatypes that cannot be re-located in memory (with realloc)
+
+template<class T>
+class bvec {
+
+    static inline int imin(int x, int y) {
+        int mask = (x-y) >> (sizeof(int)*8-1);
+        return (x&mask) + (y&(~mask)); }
+
+    static inline int imax(int x, int y) {
+        int mask = (y-x) >> (sizeof(int)*8-1);
+        return (x&mask) + (y&(~mask)); }
+
+    struct Vec_t {
+        int sz;
+        int cap;
+        T   data[0];
+
+        static Vec_t* alloc(Vec_t* x, int size){
+            x = (Vec_t*)realloc((void*)x, sizeof(Vec_t) + sizeof(T)*size);
+            x->cap = size;
+            return x;
+        }
+        
+    };
+
+    Vec_t* ref;
+
+    static const int init_size = 2;
+    static int   nextSize (int current) { return (current * 3 + 1) >> 1; }
+    static int   fitSize  (int needed)  { int x; for (x = init_size; needed > x; x = nextSize(x)); return x; }
+
+    void fill (int size) {
+        assert(ref != NULL);
+        for (T* i = ref->data; i < ref->data + size; i++)
+            new (i) T();
+    }
+
+    void fill (int size, const T& pad) {
+        assert(ref != NULL);
+        for (T* i = ref->data; i < ref->data + size; i++)
+            new (i) T(pad);
+    }
+
+    // Don't allow copying (error prone):
+    altvec<T>&  operator = (altvec<T>& other) { assert(0); }
+    altvec (altvec<T>& other)                  { assert(0); }
+
+public:
+    void     clear  (bool dealloc = false) { 
+        if (ref != NULL){
+            for (int i = 0; i < ref->sz; i++) 
+                (*ref).data[i].~T();
+
+            if (dealloc) { 
+                free(ref); ref = NULL; 
+            }else 
+                ref->sz = 0;
+        } 
+    }
+
+    // Constructors:
+    altvec(void)                   : ref (NULL) { }
+    altvec(int size)               : ref (Vec_t::alloc(NULL, fitSize(size))) { fill(size);      ref->sz = size; }
+    altvec(int size, const T& pad) : ref (Vec_t::alloc(NULL, fitSize(size))) { fill(size, pad); ref->sz = size; }
+   ~altvec(void) { clear(true); }
+
+    // Ownership of underlying array:
+    operator T*       (void)           { return ref->data; }     // (unsafe but convenient)
+    operator const T* (void) const     { return ref->data; }
+
+    // Size operations:
+    int      size   (void) const       { return ref != NULL ? ref->sz : 0; }
+
+    void     pop    (void)             { assert(ref != NULL && ref->sz > 0); int last = --ref->sz; ref->data[last].~T(); }
+    void     push   (const T& elem) {
+        int size = ref != NULL ? ref->sz  : 0;
+        int cap  = ref != NULL ? ref->cap : 0;
+        if (size == cap){
+            cap = cap != 0 ? nextSize(cap) : init_size;
+            ref = Vec_t::alloc(ref, cap); 
+        }
+        //new (&ref->data[size]) T(elem); 
+        ref->data[size] = elem; 
+        ref->sz = size+1; 
+    }
+
+    void     push   () {
+        int size = ref != NULL ? ref->sz  : 0;
+        int cap  = ref != NULL ? ref->cap : 0;
+        if (size == cap){
+            cap = cap != 0 ? nextSize(cap) : init_size;
+            ref = Vec_t::alloc(ref, cap); 
+        }
+        new (&ref->data[size]) T(); 
+        ref->sz = size+1; 
+    }
+
+    void     shrink (int nelems)             { for (int i = 0; i < nelems; i++) pop(); }
+    void     shrink_(int nelems)             { for (int i = 0; i < nelems; i++) pop(); }
+    void     growTo (int size)               { while (this->size() < size) push(); }
+    void     growTo (int size, const T& pad) { while (this->size() < size) push(pad); }
+    void     capacity (int size)             { growTo(size); }
+
+    const T& last  (void) const              { return ref->data[ref->sz-1]; }
+    T&       last  (void)                    { return ref->data[ref->sz-1]; }
+
+    // Vector interface:
+    const T& operator [] (int index) const  { return ref->data[index]; }
+    T&       operator [] (int index)        { return ref->data[index]; }
+
+    void copyTo(altvec<T>& copy) const { copy.clear(); for (int i = 0; i < size(); i++) copy.push(ref->data[i]); }
+    void moveTo(altvec<T>& dest) { dest.clear(true); dest.ref = ref; ref = NULL; }
+
+};
+
+
+#endif
diff --git a/minisat/include/Heap.h b/minisat/include/Heap.h
new file mode 100644
index 0000000..b07ccd1
--- /dev/null
+++ b/minisat/include/Heap.h
@@ -0,0 +1,169 @@
+/******************************************************************************************[Heap.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Heap_h
+#define Heap_h
+
+#include "Vec.h"
+
+//=================================================================================================
+// A heap implementation with support for decrease/increase key.
+
+
+template<class Comp>
+class Heap {
+    Comp     lt;
+    vec<int> heap;     // heap of ints
+    vec<int> indices;  // int -> index in heap
+
+    // Index "traversal" functions
+    static inline int left  (int i) { return i*2+1; }
+    static inline int right (int i) { return (i+1)*2; }
+    static inline int parent(int i) { return (i-1) >> 1; }
+
+
+    inline void percolateUp(int i)
+    {
+        int x = heap[i];
+        while (i != 0 && lt(x, heap[parent(i)])){
+            heap[i]          = heap[parent(i)];
+            indices[heap[i]] = i;
+            i                = parent(i);
+        }
+        heap   [i] = x;
+        indices[x] = i;
+    }
+
+
+    inline void percolateDown(int i)
+    {
+        int x = heap[i];
+        while (left(i) < heap.size()){
+            int child = right(i) < heap.size() && lt(heap[right(i)], heap[left(i)]) ? right(i) : left(i);
+            if (!lt(heap[child], x)) break;
+            heap[i]          = heap[child];
+            indices[heap[i]] = i;
+            i                = child;
+        }
+        heap   [i] = x;
+        indices[x] = i;
+    }
+
+
+    bool heapProperty (int i) const {
+        return i >= heap.size()
+            || ((i == 0 || !lt(heap[i], heap[parent(i)])) && heapProperty(left(i)) && heapProperty(right(i))); }
+
+
+  public:
+    Heap(const Comp& c) : lt(c) { }
+
+    int  size      ()          const { return heap.size(); }
+    bool empty     ()          const { return heap.size() == 0; }
+    bool inHeap    (int n)     const { return n < indices.size() && indices[n] >= 0; }
+    int  operator[](int index) const { assert(index < heap.size()); return heap[index]; }
+
+    void decrease  (int n) { assert(inHeap(n)); percolateUp(indices[n]); }
+
+    // RENAME WHEN THE DEPRECATED INCREASE IS REMOVED.
+    void increase_ (int n) { assert(inHeap(n)); percolateDown(indices[n]); }
+
+
+    void insert(int n)
+    {
+        indices.growTo(n+1, -1);
+        assert(!inHeap(n));
+
+        indices[n] = heap.size();
+        heap.push(n);
+        percolateUp(indices[n]); 
+    }
+
+
+    int  removeMin()
+    {
+        int x            = heap[0];
+        heap[0]          = heap.last();
+        indices[heap[0]] = 0;
+        indices[x]       = -1;
+        heap.pop();
+        if (heap.size() > 1) percolateDown(0);
+        return x; 
+    }
+
+
+    void clear(bool dealloc = false) 
+    { 
+        for (int i = 0; i < heap.size(); i++)
+            indices[heap[i]] = -1;
+#ifdef NDEBUG
+        for (int i = 0; i < indices.size(); i++)
+            assert(indices[i] == -1);
+#endif
+        heap.clear(dealloc); 
+    }
+
+
+    // Fool proof variant of insert/decrease/increase
+    void update (int n)
+    {
+        if (!inHeap(n))
+            insert(n);
+        else {
+            percolateUp(indices[n]);
+            percolateDown(indices[n]);
+        }
+    }
+
+
+    // Delete elements from the heap using a given filter function (-object).
+    // *** this could probaly be replaced with a more general "buildHeap(vec<int>&)" method ***
+    template <class F>
+    void filter(const F& filt) {
+        int i,j;
+        for (i = j = 0; i < heap.size(); i++)
+            if (filt(heap[i])){
+                heap[j]          = heap[i];
+                indices[heap[i]] = j++;
+            }else
+                indices[heap[i]] = -1;
+
+        heap.shrink(i - j);
+        for (int i = heap.size() / 2 - 1; i >= 0; i--)
+            percolateDown(i);
+
+        assert(heapProperty());
+    }
+
+
+    // DEBUG: consistency checking
+    bool heapProperty() const {
+        return heapProperty(1); }
+
+
+    // COMPAT: should be removed
+    void setBounds (int n) { }
+    void increase  (int n) { decrease(n); }
+    int  getmin    ()      { return removeMin(); }
+
+};
+
+
+//=================================================================================================
+#endif
diff --git a/minisat/include/Map.h b/minisat/include/Map.h
new file mode 100644
index 0000000..b6d76a3
--- /dev/null
+++ b/minisat/include/Map.h
@@ -0,0 +1,118 @@
+/*******************************************************************************************[Map.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Map_h
+#define Map_h
+
+#include <stdint.h>
+
+#include "Vec.h"
+
+//=================================================================================================
+// Default hash/equals functions
+//
+
+template<class K> struct Hash  { uint32_t operator()(const K& k)               const { return hash(k);  } };
+template<class K> struct Equal { bool     operator()(const K& k1, const K& k2) const { return k1 == k2; } };
+
+template<class K> struct DeepHash  { uint32_t operator()(const K* k)               const { return hash(*k);  } };
+template<class K> struct DeepEqual { bool     operator()(const K* k1, const K* k2) const { return *k1 == *k2; } };
+
+//=================================================================================================
+// Some primes
+//
+
+static const int nprimes          = 25;
+static const int primes [nprimes] = { 31, 73, 151, 313, 643, 1291, 2593, 5233, 10501, 21013, 42073, 84181, 168451, 337219, 674701, 1349473, 2699299, 5398891, 10798093, 21596719, 43193641, 86387383, 172775299, 345550609, 691101253 };
+
+//=================================================================================================
+// Hash table implementation of Maps
+//
+
+template<class K, class D, class H = Hash<K>, class E = Equal<K> >
+class Map {
+    struct Pair { K key; D data; };
+
+    H          hash;
+    E          equals;
+
+    vec<Pair>* table;
+    int        cap;
+    int        size;
+
+    // Don't allow copying (error prone):
+    Map<K,D,H,E>&  operator = (Map<K,D,H,E>& other) { assert(0); }
+                   Map        (Map<K,D,H,E>& other) { assert(0); }
+
+    int32_t index  (const K& k) const { return hash(k) % cap; }
+    void   _insert (const K& k, const D& d) { table[index(k)].push(); table[index(k)].last().key = k; table[index(k)].last().data = d; }
+    void    rehash () {
+        const vec<Pair>* old = table;
+
+        int newsize = primes[0];
+        for (int i = 1; newsize <= cap && i < nprimes; i++)
+           newsize = primes[i];
+
+        table = new vec<Pair>[newsize];
+
+        for (int i = 0; i < cap; i++){
+            for (int j = 0; j < old[i].size(); j++){
+                _insert(old[i][j].key, old[i][j].data); }}
+
+        delete [] old;
+
+        cap = newsize;
+    }
+
+    
+    public:
+
+     Map () : table(NULL), cap(0), size(0) {}
+     Map (const H& h, const E& e) : Map(), hash(h), equals(e) {}
+    ~Map () { delete [] table; }
+
+    void insert (const K& k, const D& d) { if (size+1 > cap / 2) rehash(); _insert(k, d); size++; }
+    bool peek   (const K& k, D& d) {
+        if (size == 0) return false;
+        const vec<Pair>& ps = table[index(k)];
+        for (int i = 0; i < ps.size(); i++)
+            if (equals(ps[i].key, k)){
+                d = ps[i].data;
+                return true; } 
+        return false;
+    }
+
+    void remove (const K& k) {
+        assert(table != NULL);
+        vec<Pair>& ps = table[index(k)];
+        int j = 0;
+        for (; j < ps.size() && !equals(ps[j].key, k); j++);
+        assert(j < ps.size());
+        ps[j] = ps.last();
+        ps.pop();
+    }
+
+    void clear  () {
+        cap = size = 0;
+        delete [] table;
+        table = NULL;
+    }
+};
+
+#endif
diff --git a/minisat/include/Queue.h b/minisat/include/Queue.h
new file mode 100644
index 0000000..2cc110c
--- /dev/null
+++ b/minisat/include/Queue.h
@@ -0,0 +1,82 @@
+/*****************************************************************************************[Queue.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Queue_h
+#define Queue_h
+
+#include "Vec.h"
+
+//=================================================================================================
+
+
+template <class T>
+class Queue {
+    vec<T>  elems;
+    int     first;
+
+public:
+    Queue(void) : first(0) { }
+
+    void insert(T x)   { elems.push(x); }
+    T    peek  () const { return elems[first]; }
+    void pop   () { first++; }
+
+    void clear(bool dealloc = false)   { elems.clear(dealloc); first = 0; }
+    int  size(void)    { return elems.size() - first; }
+
+    //bool has(T x) { for (int i = first; i < elems.size(); i++) if (elems[i] == x) return true; return false; }
+
+    const T& operator [] (int index) const  { return elems[first + index]; }
+
+};
+
+//template<class T>
+//class Queue {
+//    vec<T>  buf;
+//    int     first;
+//    int     end;
+//
+//public:
+//    typedef T Key;
+//
+//    Queue() : buf(1), first(0), end(0) {}
+//
+//    void clear () { buf.shrinkTo(1); first = end = 0; }
+//    int  size  () { return (end >= first) ? end - first : end - first + buf.size(); }
+//
+//    T    peek  () { assert(first != end); return buf[first]; }
+//    void pop   () { assert(first != end); first++; if (first == buf.size()) first = 0; }
+//    void insert(T elem) {   // INVARIANT: buf[end] is always unused
+//        buf[end++] = elem;
+//        if (end == buf.size()) end = 0;
+//        if (first == end){  // Resize:
+//            vec<T>  tmp((buf.size()*3 + 1) >> 1);
+//            //**/printf("queue alloc: %d elems (%.1f MB)\n", tmp.size(), tmp.size() * sizeof(T) / 1000000.0);
+//            int     i = 0;
+//            for (int j = first; j < buf.size(); j++) tmp[i++] = buf[j];
+//            for (int j = 0    ; j < end       ; j++) tmp[i++] = buf[j];
+//            first = 0;
+//            end   = buf.size();
+//            tmp.moveTo(buf);
+//        }
+//    }
+//};
+
+//=================================================================================================
+#endif
diff --git a/minisat/include/Sort.h b/minisat/include/Sort.h
new file mode 100644
index 0000000..1f301f5
--- /dev/null
+++ b/minisat/include/Sort.h
@@ -0,0 +1,93 @@
+/******************************************************************************************[Sort.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Sort_h
+#define Sort_h
+
+#include "Vec.h"
+
+//=================================================================================================
+// Some sorting algorithms for vec's
+
+
+template<class T>
+struct LessThan_default {
+    bool operator () (T x, T y) { return x < y; }
+};
+
+
+template <class T, class LessThan>
+void selectionSort(T* array, int size, LessThan lt)
+{
+    int     i, j, best_i;
+    T       tmp;
+
+    for (i = 0; i < size-1; i++){
+        best_i = i;
+        for (j = i+1; j < size; j++){
+            if (lt(array[j], array[best_i]))
+                best_i = j;
+        }
+        tmp = array[i]; array[i] = array[best_i]; array[best_i] = tmp;
+    }
+}
+template <class T> static inline void selectionSort(T* array, int size) {
+    selectionSort(array, size, LessThan_default<T>()); }
+
+template <class T, class LessThan>
+void sort(T* array, int size, LessThan lt)
+{
+    if (size <= 15)
+        selectionSort(array, size, lt);
+
+    else{
+        T           pivot = array[size / 2];
+        T           tmp;
+        int         i = -1;
+        int         j = size;
+
+        for(;;){
+            do i++; while(lt(array[i], pivot));
+            do j--; while(lt(pivot, array[j]));
+
+            if (i >= j) break;
+
+            tmp = array[i]; array[i] = array[j]; array[j] = tmp;
+        }
+
+        sort(array    , i     , lt);
+        sort(&array[i], size-i, lt);
+    }
+}
+template <class T> static inline void sort(T* array, int size) {
+    sort(array, size, LessThan_default<T>()); }
+
+
+//=================================================================================================
+// For 'vec's:
+
+
+template <class T, class LessThan> void sort(vec<T>& v, LessThan lt) {
+    sort((T*)v, v.size(), lt); }
+template <class T> void sort(vec<T>& v) {
+    sort(v, LessThan_default<T>()); }
+
+
+//=================================================================================================
+#endif
diff --git a/minisat/include/Vec.h b/minisat/include/Vec.h
new file mode 100644
index 0000000..e780aa1
--- /dev/null
+++ b/minisat/include/Vec.h
@@ -0,0 +1,133 @@
+/*******************************************************************************************[Vec.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Vec_h
+#define Vec_h
+
+#include <cstdlib>
+#include <cassert>
+#include <new>
+
+//=================================================================================================
+// Automatically resizable arrays
+//
+// NOTE! Don't use this vector on datatypes that cannot be re-located in memory (with realloc)
+
+template<class T>
+class vec {
+    T*  data;
+    int sz;
+    int cap;
+
+    void     init(int size, const T& pad);
+    void     grow(int min_cap);
+
+    // Don't allow copying (error prone):
+    vec<T>&  operator = (vec<T>& other) { assert(0); return *this; }
+             vec        (vec<T>& other) { assert(0); }
+
+    static inline int imin(int x, int y) {
+        int mask = (x-y) >> (sizeof(int)*8-1);
+        return (x&mask) + (y&(~mask)); }
+
+    static inline int imax(int x, int y) {
+        int mask = (y-x) >> (sizeof(int)*8-1);
+        return (x&mask) + (y&(~mask)); }
+
+public:
+    // Types:
+    typedef int Key;
+    typedef T   Datum;
+
+    // Constructors:
+    vec(void)                   : data(NULL) , sz(0)   , cap(0)    { }
+    vec(int size)               : data(NULL) , sz(0)   , cap(0)    { growTo(size); }
+    vec(int size, const T& pad) : data(NULL) , sz(0)   , cap(0)    { growTo(size, pad); }
+    vec(T* array, int size)     : data(array), sz(size), cap(size) { }      // (takes ownership of array -- will be deallocated with 'free()')
+   ~vec(void)                                                      { clear(true); }
+
+    // Ownership of underlying array:
+    T*       release  (void)           { T* ret = data; data = NULL; sz = 0; cap = 0; return ret; }
+    operator T*       (void)           { return data; }     // (unsafe but convenient)
+    operator const T* (void) const     { return data; }
+
+    // Size operations:
+    int      size   (void) const       { return sz; }
+    void     shrink (int nelems)       { assert(nelems <= sz); for (int i = 0; i < nelems; i++) sz--, data[sz].~T(); }
+    void     shrink_(int nelems)       { assert(nelems <= sz); sz -= nelems; }
+    void     pop    (void)             { sz--, data[sz].~T(); }
+    void     growTo (int size);
+    void     growTo (int size, const T& pad);
+    void     clear  (bool dealloc = false);
+    void     capacity (int size) { grow(size); }
+
+    // Stack interface:
+#if 1
+    void     push  (void)              { if (sz == cap) { cap = imax(2, (cap*3+1)>>1); data = (T*)realloc(data, cap * sizeof(T)); } new (&data[sz]) T(); sz++; }
+    //void     push  (const T& elem)     { if (sz == cap) { cap = imax(2, (cap*3+1)>>1); data = (T*)realloc(data, cap * sizeof(T)); } new (&data[sz]) T(elem); sz++; }
+    void     push  (const T& elem)     { if (sz == cap) { cap = imax(2, (cap*3+1)>>1); data = (T*)realloc(data, cap * sizeof(T)); } data[sz++] = elem; }
+    void     push_ (const T& elem)     { assert(sz < cap); data[sz++] = elem; }
+#else
+    void     push  (void)              { if (sz == cap) grow(sz+1); new (&data[sz]) T()    ; sz++; }
+    void     push  (const T& elem)     { if (sz == cap) grow(sz+1); new (&data[sz]) T(elem); sz++; }
+#endif
+
+    const T& last  (void) const        { return data[sz-1]; }
+    T&       last  (void)              { return data[sz-1]; }
+
+    // Vector interface:
+    const T& operator [] (int index) const  { return data[index]; }
+    T&       operator [] (int index)        { return data[index]; }
+
+
+    // Duplicatation (preferred instead):
+    void copyTo(vec<T>& copy) const { copy.clear(); copy.growTo(sz); for (int i = 0; i < sz; i++) new (&copy[i]) T(data[i]); }
+    void moveTo(vec<T>& dest) { dest.clear(true); dest.data = data; dest.sz = sz; dest.cap = cap; data = NULL; sz = 0; cap = 0; }
+};
+
+template<class T>
+void vec<T>::grow(int min_cap) {
+    if (min_cap <= cap) return;
+    if (cap == 0) cap = (min_cap >= 2) ? min_cap : 2;
+    else          do cap = (cap*3+1) >> 1; while (cap < min_cap);
+    data = (T*)realloc(data, cap * sizeof(T)); }
+
+template<class T>
+void vec<T>::growTo(int size, const T& pad) {
+    if (sz >= size) return;
+    grow(size);
+    for (int i = sz; i < size; i++) new (&data[i]) T(pad);
+    sz = size; }
+
+template<class T>
+void vec<T>::growTo(int size) {
+    if (sz >= size) return;
+    grow(size);
+    for (int i = sz; i < size; i++) new (&data[i]) T();
+    sz = size; }
+
+template<class T>
+void vec<T>::clear(bool dealloc) {
+    if (data != NULL){
+        for (int i = 0; i < sz; i++) data[i].~T();
+        sz = 0;
+        if (dealloc) free(data), data = NULL, cap = 0; } }
+
+
+#endif
diff --git a/minisat/solver/Solver.C b/minisat/solver/Solver.C
new file mode 100644
index 0000000..54b45d9
--- /dev/null
+++ b/minisat/solver/Solver.C
@@ -0,0 +1,746 @@
+/****************************************************************************************[Solver.C]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#include "Solver.H"
+#include "Sort.h"
+#include <cmath>
+
+
+//=================================================================================================
+// Constructor/Destructor:
+
+
+Solver::Solver() :
+
+    // Parameters: (formerly in 'SearchParams')
+    var_decay(1 / 0.95), clause_decay(1 / 0.999), random_var_freq(0.02)
+  , restart_first(100), restart_inc(1.5), learntsize_factor((double)1/(double)3), learntsize_inc(1.1)
+
+    // More parameters:
+    //
+  , expensive_ccmin  (true)
+  , polarity_mode    (polarity_false)
+  , verbosity        (0)
+
+    // Statistics: (formerly in 'SolverStats')
+    //
+  , starts(0), decisions(0), rnd_decisions(0), propagations(0), conflicts(0)
+  , clauses_literals(0), learnts_literals(0), max_literals(0), tot_literals(0)
+
+  , ok               (true)
+  , cla_inc          (1)
+  , var_inc          (1)
+  , qhead            (0)
+  , simpDB_assigns   (-1)
+  , simpDB_props     (0)
+  , order_heap       (VarOrderLt(activity))
+  , random_seed      (91648253)
+  , progress_estimate(0)
+  , remove_satisfied (true)
+{}
+
+
+Solver::~Solver()
+{
+    for (int i = 0; i < learnts.size(); i++) free(learnts[i]);
+    for (int i = 0; i < clauses.size(); i++) free(clauses[i]);
+}
+
+
+//=================================================================================================
+// Minor methods:
+
+
+// Creates a new SAT variable in the solver. If 'decision_var' is cleared, variable will not be
+// used as a decision variable (NOTE! This has effects on the meaning of a SATISFIABLE result).
+//
+Var Solver::newVar(bool sign, bool dvar)
+{
+    int v = nVars();
+    watches   .push();          // (list for positive literal)
+    watches   .push();          // (list for negative literal)
+    reason    .push(NULL);
+    assigns   .push(toInt(l_Undef));
+    level     .push(-1);
+    activity  .push(0);
+    seen      .push(0);
+
+    polarity    .push((char)sign);
+    decision_var.push((char)dvar);
+
+    insertVarOrder(v);
+    return v;
+}
+
+
+bool Solver::addClause(vec<Lit>& ps)
+{
+    assert(decisionLevel() == 0);
+
+    if (!ok)
+        return false;
+    else{
+        // Check if clause is satisfied and remove false/duplicate literals:
+        sort(ps);
+        Lit p; int i, j;
+        for (i = j = 0, p = lit_Undef; i < ps.size(); i++)
+            if (value(ps[i]) == l_True || ps[i] == ~p)
+                return true;
+            else if (value(ps[i]) != l_False && ps[i] != p)
+                ps[j++] = p = ps[i];
+        ps.shrink(i - j);
+    }
+
+    if (ps.size() == 0)
+        return ok = false;
+    else if (ps.size() == 1){
+        assert(value(ps[0]) == l_Undef);
+        uncheckedEnqueue(ps[0]);
+        return ok = (propagate() == NULL);
+    }else{
+        Clause* c = Clause_new(ps, false);
+        clauses.push(c);
+        attachClause(*c);
+    }
+
+    return true;
+}
+
+
+void Solver::attachClause(Clause& c) {
+    assert(c.size() > 1);
+    watches[toInt(~c[0])].push(&c);
+    watches[toInt(~c[1])].push(&c);
+    if (c.learnt()) learnts_literals += c.size();
+    else            clauses_literals += c.size(); }
+
+
+void Solver::detachClause(Clause& c) {
+    assert(c.size() > 1);
+    assert(find(watches[toInt(~c[0])], &c));
+    assert(find(watches[toInt(~c[1])], &c));
+    remove(watches[toInt(~c[0])], &c);
+    remove(watches[toInt(~c[1])], &c);
+    if (c.learnt()) learnts_literals -= c.size();
+    else            clauses_literals -= c.size(); }
+
+
+void Solver::removeClause(Clause& c) {
+    detachClause(c);
+    free(&c); }
+
+
+bool Solver::satisfied(const Clause& c) const {
+    for (int i = 0; i < c.size(); i++)
+        if (value(c[i]) == l_True)
+            return true;
+    return false; }
+
+
+// Revert to the state at given level (keeping all assignment at 'level' but not beyond).
+//
+void Solver::cancelUntil(int level) {
+    if (decisionLevel() > level){
+        for (int c = trail.size()-1; c >= trail_lim[level]; c--){
+            Var     x  = var(trail[c]);
+            assigns[x] = toInt(l_Undef);
+            insertVarOrder(x); }
+        qhead = trail_lim[level];
+        trail.shrink(trail.size() - trail_lim[level]);
+        trail_lim.shrink(trail_lim.size() - level);
+    } }
+
+
+//=================================================================================================
+// Major methods:
+
+
+Lit Solver::pickBranchLit(int polarity_mode, double random_var_freq)
+{
+    Var next = var_Undef;
+
+    // Random decision:
+    if (drand(random_seed) < random_var_freq && !order_heap.empty()){
+        next = order_heap[irand(random_seed,order_heap.size())];
+        if (toLbool(assigns[next]) == l_Undef && decision_var[next])
+            rnd_decisions++; }
+
+    // Activity based decision:
+    while (next == var_Undef || toLbool(assigns[next]) != l_Undef || !decision_var[next])
+        if (order_heap.empty()){
+            next = var_Undef;
+            break;
+        }else
+            next = order_heap.removeMin();
+
+    bool sign = false;
+    switch (polarity_mode){
+    case polarity_true:  sign = false; break;
+    case polarity_false: sign = true;  break;
+    case polarity_user:  sign = polarity[next]; break;
+    case polarity_rnd:   sign = irand(random_seed, 2); break;
+    default: assert(false); }
+
+    return next == var_Undef ? lit_Undef : Lit(next, sign);
+}
+
+
+/*_________________________________________________________________________________________________
+|
+|  analyze : (confl : Clause*) (out_learnt : vec<Lit>&) (out_btlevel : int&)  ->  [void]
+|  
+|  Description:
+|    Analyze conflict and produce a reason clause.
+|  
+|    Pre-conditions:
+|      * 'out_learnt' is assumed to be cleared.
+|      * Current decision level must be greater than root level.
+|  
+|    Post-conditions:
+|      * 'out_learnt[0]' is the asserting literal at level 'out_btlevel'.
+|  
+|  Effect:
+|    Will undo part of the trail, upto but not beyond the assumption of the current decision level.
+|________________________________________________________________________________________________@*/
+void Solver::analyze(Clause* confl, vec<Lit>& out_learnt, int& out_btlevel)
+{
+    int pathC = 0;
+    Lit p     = lit_Undef;
+
+    // Generate conflict clause:
+    //
+    out_learnt.push();      // (leave room for the asserting literal)
+    int index   = trail.size() - 1;
+    out_btlevel = 0;
+
+    do{
+        assert(confl != NULL);          // (otherwise should be UIP)
+        Clause& c = *confl;
+
+        if (c.learnt())
+            claBumpActivity(c);
+
+        for (int j = (p == lit_Undef) ? 0 : 1; j < c.size(); j++){
+            Lit q = c[j];
+
+            if (!seen[var(q)] && level[var(q)] > 0){
+                varBumpActivity(var(q));
+                seen[var(q)] = 1;
+                if (level[var(q)] >= decisionLevel())
+                    pathC++;
+                else{
+                    out_learnt.push(q);
+                    if (level[var(q)] > out_btlevel)
+                        out_btlevel = level[var(q)];
+                }
+            }
+        }
+
+        // Select next clause to look at:
+        while (!seen[var(trail[index--])]);
+        p     = trail[index+1];
+        confl = reason[var(p)];
+        seen[var(p)] = 0;
+        pathC--;
+
+    }while (pathC > 0);
+    out_learnt[0] = ~p;
+
+    // Simplify conflict clause:
+    //
+    int i, j;
+    if (expensive_ccmin){
+        uint32_t abstract_level = 0;
+        for (i = 1; i < out_learnt.size(); i++)
+            abstract_level |= abstractLevel(var(out_learnt[i])); // (maintain an abstraction of levels involved in conflict)
+
+        out_learnt.copyTo(analyze_toclear);
+        for (i = j = 1; i < out_learnt.size(); i++)
+            if (reason[var(out_learnt[i])] == NULL || !litRedundant(out_learnt[i], abstract_level))
+                out_learnt[j++] = out_learnt[i];
+    }else{
+        out_learnt.copyTo(analyze_toclear);
+        for (i = j = 1; i < out_learnt.size(); i++){
+            Clause& c = *reason[var(out_learnt[i])];
+            for (int k = 1; k < c.size(); k++)
+                if (!seen[var(c[k])] && level[var(c[k])] > 0){
+                    out_learnt[j++] = out_learnt[i];
+                    break; }
+        }
+    }
+    max_literals += out_learnt.size();
+    out_learnt.shrink(i - j);
+    tot_literals += out_learnt.size();
+
+    // Find correct backtrack level:
+    //
+    if (out_learnt.size() == 1)
+        out_btlevel = 0;
+    else{
+        int max_i = 1;
+        for (int i = 2; i < out_learnt.size(); i++)
+            if (level[var(out_learnt[i])] > level[var(out_learnt[max_i])])
+                max_i = i;
+        Lit p             = out_learnt[max_i];
+        out_learnt[max_i] = out_learnt[1];
+        out_learnt[1]     = p;
+        out_btlevel       = level[var(p)];
+    }
+
+
+    for (int j = 0; j < analyze_toclear.size(); j++) seen[var(analyze_toclear[j])] = 0;    // ('seen[]' is now cleared)
+}
+
+
+// Check if 'p' can be removed. 'abstract_levels' is used to abort early if the algorithm is
+// visiting literals at levels that cannot be removed later.
+bool Solver::litRedundant(Lit p, uint32_t abstract_levels)
+{
+    analyze_stack.clear(); analyze_stack.push(p);
+    int top = analyze_toclear.size();
+    while (analyze_stack.size() > 0){
+        assert(reason[var(analyze_stack.last())] != NULL);
+        Clause& c = *reason[var(analyze_stack.last())]; analyze_stack.pop();
+
+        for (int i = 1; i < c.size(); i++){
+            Lit p  = c[i];
+            if (!seen[var(p)] && level[var(p)] > 0){
+                if (reason[var(p)] != NULL && (abstractLevel(var(p)) & abstract_levels) != 0){
+                    seen[var(p)] = 1;
+                    analyze_stack.push(p);
+                    analyze_toclear.push(p);
+                }else{
+                    for (int j = top; j < analyze_toclear.size(); j++)
+                        seen[var(analyze_toclear[j])] = 0;
+                    analyze_toclear.shrink(analyze_toclear.size() - top);
+                    return false;
+                }
+            }
+        }
+    }
+
+    return true;
+}
+
+
+/*_________________________________________________________________________________________________
+|
+|  analyzeFinal : (p : Lit)  ->  [void]
+|  
+|  Description:
+|    Specialized analysis procedure to express the final conflict in terms of assumptions.
+|    Calculates the (possibly empty) set of assumptions that led to the assignment of 'p', and
+|    stores the result in 'out_conflict'.
+|________________________________________________________________________________________________@*/
+void Solver::analyzeFinal(Lit p, vec<Lit>& out_conflict)
+{
+    out_conflict.clear();
+    out_conflict.push(p);
+
+    if (decisionLevel() == 0)
+        return;
+
+    seen[var(p)] = 1;
+
+    for (int i = trail.size()-1; i >= trail_lim[0]; i--){
+        Var x = var(trail[i]);
+        if (seen[x]){
+            if (reason[x] == NULL){
+                assert(level[x] > 0);
+                out_conflict.push(~trail[i]);
+            }else{
+                Clause& c = *reason[x];
+                for (int j = 1; j < c.size(); j++)
+                    if (level[var(c[j])] > 0)
+                        seen[var(c[j])] = 1;
+            }
+            seen[x] = 0;
+        }
+    }
+
+    seen[var(p)] = 0;
+}
+
+
+void Solver::uncheckedEnqueue(Lit p, Clause* from)
+{
+    assert(value(p) == l_Undef);
+    assigns [var(p)] = toInt(lbool(!sign(p)));  // <<== abstract but not uttermost effecient
+    level   [var(p)] = decisionLevel();
+    reason  [var(p)] = from;
+    trail.push(p);
+}
+
+
+/*_________________________________________________________________________________________________
+|
+|  propagate : [void]  ->  [Clause*]
+|  
+|  Description:
+|    Propagates all enqueued facts. If a conflict arises, the conflicting clause is returned,
+|    otherwise NULL.
+|  
+|    Post-conditions:
+|      * the propagation queue is empty, even if there was a conflict.
+|________________________________________________________________________________________________@*/
+Clause* Solver::propagate()
+{
+    Clause* confl     = NULL;
+    int     num_props = 0;
+
+    while (qhead < trail.size()){
+        Lit            p   = trail[qhead++];     // 'p' is enqueued fact to propagate.
+        vec<Clause*>&  ws  = watches[toInt(p)];
+        Clause         **i, **j, **end;
+        num_props++;
+
+        for (i = j = (Clause**)ws, end = i + ws.size();  i != end;){
+            Clause& c = **i++;
+
+            // Make sure the false literal is data[1]:
+            Lit false_lit = ~p;
+            if (c[0] == false_lit)
+                c[0] = c[1], c[1] = false_lit;
+
+            assert(c[1] == false_lit);
+
+            // If 0th watch is true, then clause is already satisfied.
+            Lit first = c[0];
+            if (value(first) == l_True){
+                *j++ = &c;
+            }else{
+                // Look for new watch:
+                for (int k = 2; k < c.size(); k++)
+                    if (value(c[k]) != l_False){
+                        c[1] = c[k]; c[k] = false_lit;
+                        watches[toInt(~c[1])].push(&c);
+                        goto FoundWatch; }
+
+                // Did not find watch -- clause is unit under assignment:
+                *j++ = &c;
+                if (value(first) == l_False){
+                    confl = &c;
+                    qhead = trail.size();
+                    // Copy the remaining watches:
+                    while (i < end)
+                        *j++ = *i++;
+                }else
+                    uncheckedEnqueue(first, &c);
+            }
+        FoundWatch:;
+        }
+        ws.shrink(i - j);
+    }
+    propagations += num_props;
+    simpDB_props -= num_props;
+
+    return confl;
+}
+
+/*_________________________________________________________________________________________________
+|
+|  reduceDB : ()  ->  [void]
+|  
+|  Description:
+|    Remove half of the learnt clauses, minus the clauses locked by the current assignment. Locked
+|    clauses are clauses that are reason to some assignment. Binary clauses are never removed.
+|________________________________________________________________________________________________@*/
+struct reduceDB_lt { bool operator () (Clause* x, Clause* y) { return x->size() > 2 && (y->size() == 2 || x->activity() < y->activity()); } };
+void Solver::reduceDB()
+{
+    int     i, j;
+    double  extra_lim = cla_inc / learnts.size();    // Remove any clause below this activity
+
+    sort(learnts, reduceDB_lt());
+    for (i = j = 0; i < learnts.size() / 2; i++){
+        if (learnts[i]->size() > 2 && !locked(*learnts[i]))
+            removeClause(*learnts[i]);
+        else
+            learnts[j++] = learnts[i];
+    }
+    for (; i < learnts.size(); i++){
+        if (learnts[i]->size() > 2 && !locked(*learnts[i]) && learnts[i]->activity() < extra_lim)
+            removeClause(*learnts[i]);
+        else
+            learnts[j++] = learnts[i];
+    }
+    learnts.shrink(i - j);
+}
+
+
+void Solver::removeSatisfied(vec<Clause*>& cs)
+{
+    int i,j;
+    for (i = j = 0; i < cs.size(); i++){
+        if (satisfied(*cs[i]))
+            removeClause(*cs[i]);
+        else
+            cs[j++] = cs[i];
+    }
+    cs.shrink(i - j);
+}
+
+
+/*_________________________________________________________________________________________________
+|
+|  simplify : [void]  ->  [bool]
+|  
+|  Description:
+|    Simplify the clause database according to the current top-level assigment. Currently, the only
+|    thing done here is the removal of satisfied clauses, but more things can be put here.
+|________________________________________________________________________________________________@*/
+bool Solver::simplify()
+{
+    assert(decisionLevel() == 0);
+
+    if (!ok || propagate() != NULL)
+        return ok = false;
+
+    if (nAssigns() == simpDB_assigns || (simpDB_props > 0))
+        return true;
+
+    // Remove satisfied clauses:
+    removeSatisfied(learnts);
+    if (remove_satisfied)        // Can be turned off.
+        removeSatisfied(clauses);
+
+    // Remove fixed variables from the variable heap:
+    order_heap.filter(VarFilter(*this));
+
+    simpDB_assigns = nAssigns();
+    simpDB_props   = clauses_literals + learnts_literals;   // (shouldn't depend on stats really, but it will do for now)
+
+    return true;
+}
+
+
+/*_________________________________________________________________________________________________
+|
+|  search : (nof_conflicts : int) (nof_learnts : int) (params : const SearchParams&)  ->  [lbool]
+|  
+|  Description:
+|    Search for a model the specified number of conflicts, keeping the number of learnt clauses
+|    below the provided limit. NOTE! Use negative value for 'nof_conflicts' or 'nof_learnts' to
+|    indicate infinity.
+|  
+|  Output:
+|    'l_True' if a partial assigment that is consistent with respect to the clauseset is found. If
+|    all variables are decision variables, this means that the clause set is satisfiable. 'l_False'
+|    if the clause set is unsatisfiable. 'l_Undef' if the bound on number of conflicts is reached.
+|________________________________________________________________________________________________@*/
+lbool Solver::search(int nof_conflicts, int nof_learnts)
+{
+    assert(ok);
+    int         backtrack_level;
+    int         conflictC = 0;
+    vec<Lit>    learnt_clause;
+
+    starts++;
+
+    bool first = true;
+    (void)first;
+
+    for (;;){
+        Clause* confl = propagate();
+        if (confl != NULL){
+            // CONFLICT
+            conflicts++; conflictC++;
+            if (decisionLevel() == 0) return l_False;
+
+            first = false;
+
+            learnt_clause.clear();
+            analyze(confl, learnt_clause, backtrack_level);
+            cancelUntil(backtrack_level);
+            assert(value(learnt_clause[0]) == l_Undef);
+
+            if (learnt_clause.size() == 1){
+                uncheckedEnqueue(learnt_clause[0]);
+            }else{
+                Clause* c = Clause_new(learnt_clause, true);
+                learnts.push(c);
+                attachClause(*c);
+                claBumpActivity(*c);
+                uncheckedEnqueue(learnt_clause[0], c);
+            }
+
+            varDecayActivity();
+            claDecayActivity();
+
+        }else{
+            // NO CONFLICT
+
+            if (nof_conflicts >= 0 && conflictC >= nof_conflicts){
+                // Reached bound on number of conflicts:
+                progress_estimate = progressEstimate();
+                cancelUntil(0);
+                return l_Undef; }
+
+            // Simplify the set of problem clauses:
+            if (decisionLevel() == 0 && !simplify())
+                return l_False;
+
+            if (nof_learnts >= 0 && learnts.size()-nAssigns() >= nof_learnts)
+                // Reduce the set of learnt clauses:
+                reduceDB();
+
+            Lit next = lit_Undef;
+            while (decisionLevel() < assumptions.size()){
+                // Perform user provided assumption:
+                Lit p = assumptions[decisionLevel()];
+                if (value(p) == l_True){
+                    // Dummy decision level:
+                    newDecisionLevel();
+                }else if (value(p) == l_False){
+                    analyzeFinal(~p, conflict);
+                    return l_False;
+                }else{
+                    next = p;
+                    break;
+                }
+            }
+
+            if (next == lit_Undef){
+                // New variable decision:
+                decisions++;
+                next = pickBranchLit(polarity_mode, random_var_freq);
+
+                if (next == lit_Undef)
+                    // Model found:
+                    return l_True;
+            }
+
+            // Increase decision level and enqueue 'next'
+            assert(value(next) == l_Undef);
+            newDecisionLevel();
+            uncheckedEnqueue(next);
+        }
+    }
+}
+
+
+double Solver::progressEstimate() const
+{
+    double  progress = 0;
+    double  F = 1.0 / nVars();
+
+    for (int i = 0; i <= decisionLevel(); i++){
+        int beg = i == 0 ? 0 : trail_lim[i - 1];
+        int end = i == decisionLevel() ? trail.size() : trail_lim[i];
+        progress += pow(F, i) * (end - beg);
+    }
+
+    return progress / nVars();
+}
+
+
+bool Solver::solve(const vec<Lit>& assumps,bool cleanup)
+{
+    model.clear();
+    conflict.clear();
+
+    if (!ok) return false;
+
+    assumps.copyTo(assumptions);
+
+    double  nof_conflicts = restart_first;
+    double  nof_learnts   = nClauses() * learntsize_factor;
+    lbool   status        = l_Undef;
+
+    if (verbosity >= 1){
+        reportf("============================[ Search Statistics ]==============================\n");
+        reportf("| Conflicts |          ORIGINAL         |          LEARNT          | Progress |\n");
+        reportf("|           |    Vars  Clauses Literals |    Limit  Clauses Lit/Cl |          |\n");
+        reportf("===============================================================================\n");
+    }
+
+    // Search:
+    while (status == l_Undef){
+        if (verbosity >= 1)
+            reportf("| %9d | %7d %8d %8d | %8d %8d %6.0f | %6.3f %% |\n", (int)conflicts, order_heap.size(), nClauses(), (int)clauses_literals, (int)nof_learnts, nLearnts(), (double)learnts_literals/nLearnts(), progress_estimate*100), fflush(stdout);
+        status = search((int)nof_conflicts, (int)nof_learnts);
+        nof_conflicts *= restart_inc;
+        nof_learnts   *= learntsize_inc;
+    }
+
+    if (verbosity >= 1)
+        reportf("===============================================================================\n");
+
+
+    if (status == l_True){
+        // Extend & copy model:
+        model.growTo(nVars());
+        for (int i = 0; i < nVars(); i++) model[i] = value(i);
+#ifndef NDEBUG
+        verifyModel();
+#endif
+    }else{
+        assert(status == l_False);
+        if (conflict.size() == 0)
+            ok = false;
+    }
+
+    if(cleanup) cancelUntil(0);
+    return status == l_True;
+}
+
+void Solver::clearTrail(){
+  cancelUntil(0);
+}
+
+//=================================================================================================
+// Debug methods:
+
+
+void Solver::verifyModel()
+{
+    bool failed = false;
+    for (int i = 0; i < clauses.size(); i++){
+        assert(clauses[i]->mark() == 0);
+        Clause& c = *clauses[i];
+        for (int j = 0; j < c.size(); j++)
+            if (modelValue(c[j]) == l_True)
+                goto next;
+
+        reportf("unsatisfied clause: ");
+        printClause(*clauses[i]);
+        reportf("\n");
+        failed = true;
+    next:;
+    }
+
+    assert(!failed);
+
+    ///reportf("Verified %d original clauses.\n", clauses.size());
+}
+
+
+void Solver::checkLiteralCount()
+{
+    // Check that sizes are calculated correctly:
+    int cnt = 0;
+    for (int i = 0; i < clauses.size(); i++)
+        if (clauses[i]->mark() == 0)
+            cnt += clauses[i]->size();
+
+    if ((int)clauses_literals != cnt){
+        fprintf(stderr, "literal count: %d, real value = %d\n", (int)clauses_literals, cnt);
+        assert((int)clauses_literals == cnt);
+    }
+}
diff --git a/minisat/solver/Solver.H b/minisat/solver/Solver.H
new file mode 100644
index 0000000..80c8337
--- /dev/null
+++ b/minisat/solver/Solver.H
@@ -0,0 +1,309 @@
+/****************************************************************************************[Solver.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+#ifndef Solver_h
+#define Solver_h
+
+#include <cstdio>
+
+#include "Vec.h"
+#include "Heap.h"
+#include "Alg.h"
+
+#include "SolverTypes.H"
+
+
+//=================================================================================================
+// Solver -- the main class:
+
+
+class Solver {
+public:
+
+    // Constructor/Destructor:
+    //
+    Solver();
+    ~Solver();
+
+    // Problem specification:
+    //
+    Var     newVar    (bool polarity = true, bool dvar = true); // Add a new variable with parameters specifying variable mode.
+    bool    addClause (vec<Lit>& ps);                           // Add a clause to the solver. NOTE! 'ps' may be shrunk by this method!
+
+    // Solving:
+    //
+    bool    simplify     ();                        // Removes already satisfied clauses.
+    bool    solve        (const vec<Lit>& assumps,bool cleanup=true); // Search for a model that respects a given set of assumptions.
+    bool    solve        ();                        // Search without assumptions.
+    bool    okay         () const;                  // FALSE means solver is in a conflicting state
+
+    void clearTrail();
+
+    // Variable mode:
+    // 
+    void    setPolarity    (Var v, bool b); // Declare which polarity the decision heuristic should use for a variable. Requires mode 'polarity_user'.
+    void    setDecisionVar (Var v, bool b); // Declare if a variable should be eligible for selection in the decision heuristic.
+
+    // Read state:
+    //
+    lbool   value      (Var x) const;       // The current value of a variable.
+    lbool   value      (Lit p) const;       // The current value of a literal.
+    lbool   modelValue (Lit p) const;       // The value of a literal in the last model. The last call to solve must have been satisfiable.
+    int     nAssigns   ()      const;       // The current number of assigned literals.
+    int     nClauses   ()      const;       // The current number of original clauses.
+    int     nLearnts   ()      const;       // The current number of learnt clauses.
+    int     nVars      ()      const;       // The current number of variables.
+
+    // Extra results: (read-only member variable)
+    //
+    vec<lbool> model;             // If problem is satisfiable, this vector contains the model (if any).
+    vec<Lit>   conflict;          // If problem is unsatisfiable (possibly under assumptions),
+                                  // this vector represent the final conflict clause expressed in the assumptions.
+    
+    //ADDED METHODS
+    int getTrailSize() const{return trail.size();}
+    int getTrailVar(int index) const{return var(trail[index]);}
+    bool getTrailSign(int index) const{return sign(trail[index]);}
+
+    // Mode of operation:
+    //
+    double    var_decay;          // Inverse of the variable activity decay factor.                                            (default 1 / 0.95)
+    double    clause_decay;       // Inverse of the clause activity decay factor.                                              (1 / 0.999)
+    double    random_var_freq;    // The frequency with which the decision heuristic tries to choose a random variable.        (default 0.02)
+    int       restart_first;      // The initial restart limit.                                                                (default 100)
+    double    restart_inc;        // The factor with which the restart limit is multiplied in each restart.                    (default 1.5)
+    double    learntsize_factor;  // The intitial limit for learnt clauses is a factor of the original clauses.                (default 1 / 3)
+    double    learntsize_inc;     // The limit for learnt clauses is multiplied with this factor each restart.                 (default 1.1)
+    bool      expensive_ccmin;    // Controls conflict clause minimization.                                                    (default TRUE)
+    int       polarity_mode;      // Controls which polarity the decision heuristic chooses. See enum below for allowed modes. (default polarity_false)
+    int       verbosity;          // Verbosity level. 0=silent, 1=some progress report                                         (default 0)
+
+    enum { polarity_true = 0, polarity_false = 1, polarity_user = 2, polarity_rnd = 3 };
+
+    // Statistics: (read-only member variable)
+    //
+    uint64_t starts, decisions, rnd_decisions, propagations, conflicts;
+    uint64_t clauses_literals, learnts_literals, max_literals, tot_literals;
+
+protected:
+
+    // Helper structures:
+    //
+    struct VarOrderLt {
+        const vec<double>&  activity;
+        bool operator () (Var x, Var y) const { return activity[x] > activity[y]; }
+        VarOrderLt(const vec<double>&  act) : activity(act) { }
+    };
+
+    friend class VarFilter;
+    struct VarFilter {
+        const Solver& s;
+        VarFilter(const Solver& _s) : s(_s) {}
+        bool operator()(Var v) const { return toLbool(s.assigns[v]) == l_Undef && s.decision_var[v]; }
+    };
+
+    // Solver state:
+    //
+    bool                ok;               // If FALSE, the constraints are already unsatisfiable. No part of the solver state may be used!
+    vec<Clause*>        clauses;          // List of problem clauses.
+    vec<Clause*>        learnts;          // List of learnt clauses.
+    double              cla_inc;          // Amount to bump next clause with.
+    vec<double>         activity;         // A heuristic measurement of the activity of a variable.
+    double              var_inc;          // Amount to bump next variable with.
+    vec<vec<Clause*> >  watches;          // 'watches[lit]' is a list of constraints watching 'lit' (will go there if literal becomes true).
+    vec<char>           assigns;          // The current assignments (lbool:s stored as char:s).
+    vec<char>           polarity;         // The preferred polarity of each variable.
+    vec<char>           decision_var;     // Declares if a variable is eligible for selection in the decision heuristic.
+    vec<Lit>            trail;            // Assignment stack; stores all assigments made in the order they were made.
+    vec<int>            trail_lim;        // Separator indices for different decision levels in 'trail'.
+    vec<Clause*>        reason;           // 'reason[var]' is the clause that implied the variables current value, or 'NULL' if none.
+    vec<int>            level;            // 'level[var]' contains the level at which the assignment was made.
+    int                 qhead;            // Head of queue (as index into the trail -- no more explicit propagation queue in MiniSat).
+    int                 simpDB_assigns;   // Number of top-level assignments since last execution of 'simplify()'.
+    int64_t             simpDB_props;     // Remaining number of propagations that must be made before next execution of 'simplify()'.
+    vec<Lit>            assumptions;      // Current set of assumptions provided to solve by the user.
+    Heap<VarOrderLt>    order_heap;       // A priority queue of variables ordered with respect to the variable activity.
+    double              random_seed;      // Used by the random variable selection.
+    double              progress_estimate;// Set by 'search()'.
+    bool                remove_satisfied; // Indicates whether possibly inefficient linear scan for satisfied clauses should be performed in 'simplify'.
+
+    // Temporaries (to reduce allocation overhead). Each variable is prefixed by the method in which it is
+    // used, exept 'seen' wich is used in several places.
+    //
+    vec<char>           seen;
+    vec<Lit>            analyze_stack;
+    vec<Lit>            analyze_toclear;
+    vec<Lit>            add_tmp;
+
+    // Main internal methods:
+    //
+    void     insertVarOrder   (Var x);                                                 // Insert a variable in the decision order priority queue.
+    Lit      pickBranchLit    (int polarity_mode, double random_var_freq);             // Return the next decision variable.
+    void     newDecisionLevel ();                                                      // Begins a new decision level.
+    void     uncheckedEnqueue (Lit p, Clause* from = NULL);                            // Enqueue a literal. Assumes value of literal is undefined.
+    bool     enqueue          (Lit p, Clause* from = NULL);                            // Test if fact 'p' contradicts current state, enqueue otherwise.
+    Clause*  propagate        ();                                                      // Perform unit propagation. Returns possibly conflicting clause.
+    void     cancelUntil      (int level);                                             // Backtrack until a certain level.
+    void     analyze          (Clause* confl, vec<Lit>& out_learnt, int& out_btlevel); // (bt = backtrack)
+    void     analyzeFinal     (Lit p, vec<Lit>& out_conflict);                         // COULD THIS BE IMPLEMENTED BY THE ORDINARIY "analyze" BY SOME REASONABLE GENERALIZATION?
+    bool     litRedundant     (Lit p, uint32_t abstract_levels);                       // (helper method for 'analyze()')
+    lbool    search           (int nof_conflicts, int nof_learnts);                    // Search for a given number of conflicts.
+    void     reduceDB         ();                                                      // Reduce the set of learnt clauses.
+    void     removeSatisfied  (vec<Clause*>& cs);                                      // Shrink 'cs' to contain only non-satisfied clauses.
+
+    // Maintaining Variable/Clause activity:
+    //
+    void     varDecayActivity ();                      // Decay all variables with the specified factor. Implemented by increasing the 'bump' value instead.
+    void     varBumpActivity  (Var v);                 // Increase a variable with the current 'bump' value.
+    void     claDecayActivity ();                      // Decay all clauses with the specified factor. Implemented by increasing the 'bump' value instead.
+    void     claBumpActivity  (Clause& c);             // Increase a clause with the current 'bump' value.
+
+    // Operations on clauses:
+    //
+    void     attachClause     (Clause& c);             // Attach a clause to watcher lists.
+    void     detachClause     (Clause& c);             // Detach a clause to watcher lists.
+    void     removeClause     (Clause& c);             // Detach and free a clause.
+    bool     locked           (const Clause& c) const; // Returns TRUE if a clause is a reason for some implication in the current state.
+    bool     satisfied        (const Clause& c) const; // Returns TRUE if a clause is satisfied in the current state.
+
+    // Misc:
+    //
+    int      decisionLevel    ()      const; // Gives the current decisionlevel.
+    uint32_t abstractLevel    (Var x) const; // Used to represent an abstraction of sets of decision levels.
+    double   progressEstimate ()      const; // DELETE THIS ?? IT'S NOT VERY USEFUL ...
+
+    // Debug:
+    void     printLit         (Lit l);
+    template<class C>
+    void     printClause      (const C& c);
+    void     verifyModel      ();
+    void     checkLiteralCount();
+
+    // Static helpers:
+    //
+
+    // Returns a random float 0 <= x < 1. Seed must never be 0.
+    static inline double drand(double& seed) {
+        seed *= 1389796;
+        int q = (int)(seed / 2147483647);
+        seed -= (double)q * 2147483647;
+        return seed / 2147483647; }
+
+    // Returns a random integer 0 <= x < size. Seed must never be 0.
+    static inline int irand(double& seed, int size) {
+        return (int)(drand(seed) * size); }
+};
+
+
+//=================================================================================================
+// Implementation of inline methods:
+
+
+inline void Solver::insertVarOrder(Var x) {
+    if (!order_heap.inHeap(x) && decision_var[x]) order_heap.insert(x); }
+
+inline void Solver::varDecayActivity() { var_inc *= var_decay; }
+inline void Solver::varBumpActivity(Var v) {
+    if ( (activity[v] += var_inc) > 1e100 ) {
+        // Rescale:
+        for (int i = 0; i < nVars(); i++)
+            activity[i] *= 1e-100;
+        var_inc *= 1e-100; }
+
+    // Update order_heap with respect to new activity:
+    if (order_heap.inHeap(v))
+        order_heap.decrease(v); }
+
+inline void Solver::claDecayActivity() { cla_inc *= clause_decay; }
+inline void Solver::claBumpActivity (Clause& c) {
+        if ( (c.activity() += cla_inc) > 1e20 ) {
+            // Rescale:
+            for (int i = 0; i < learnts.size(); i++)
+                learnts[i]->activity() *= 1e-20;
+            cla_inc *= 1e-20; } }
+
+inline bool     Solver::enqueue         (Lit p, Clause* from)   { return value(p) != l_Undef ? value(p) != l_False : (uncheckedEnqueue(p, from), true); }
+inline bool     Solver::locked          (const Clause& c) const { return reason[var(c[0])] == &c && value(c[0]) == l_True; }
+inline void     Solver::newDecisionLevel()                      { trail_lim.push(trail.size()); }
+
+inline int      Solver::decisionLevel ()      const   { return trail_lim.size(); }
+inline uint32_t Solver::abstractLevel (Var x) const   { return 1 << (level[x] & 31); }
+inline lbool    Solver::value         (Var x) const   { return toLbool(assigns[x]); }
+inline lbool    Solver::value         (Lit p) const   { return toLbool(assigns[var(p)]) ^ sign(p); }
+inline lbool    Solver::modelValue    (Lit p) const   { return model[var(p)] ^ sign(p); }
+inline int      Solver::nAssigns      ()      const   { return trail.size(); }
+inline int      Solver::nClauses      ()      const   { return clauses.size(); }
+inline int      Solver::nLearnts      ()      const   { return learnts.size(); }
+inline int      Solver::nVars         ()      const   { return assigns.size(); }
+inline void     Solver::setPolarity   (Var v, bool b) { polarity    [v] = (char)b; }
+inline void     Solver::setDecisionVar(Var v, bool b) { decision_var[v] = (char)b; if (b) { insertVarOrder(v); } }
+inline bool     Solver::solve         ()              { vec<Lit> tmp; return solve(tmp); }
+inline bool     Solver::okay          ()      const   { return ok; }
+
+
+
+//=================================================================================================
+// Debug + etc:
+
+
+#define reportf(format, args...) ( fflush(stdout), fprintf(stderr, format, ## args), fflush(stderr) )
+
+static inline void logLit(FILE* f, Lit l)
+{
+    fprintf(f, "%sx%d", sign(l) ? "~" : "", var(l)+1);
+}
+
+static inline void logLits(FILE* f, const vec<Lit>& ls)
+{
+    fprintf(f, "[ ");
+    if (ls.size() > 0){
+        logLit(f, ls[0]);
+        for (int i = 1; i < ls.size(); i++){
+            fprintf(f, ", ");
+            logLit(f, ls[i]);
+        }
+    }
+    fprintf(f, "] ");
+}
+
+static inline const char* showBool(bool b) { return b ? "true" : "false"; }
+
+
+// Just like 'assert()' but expression will be evaluated in the release version as well.
+static inline void check(bool expr) { assert(expr); }
+
+
+inline void Solver::printLit(Lit l)
+{
+    reportf("%s%d:%c", sign(l) ? "-" : "", var(l)+1, value(l) == l_True ? '1' : (value(l) == l_False ? '0' : 'X'));
+}
+
+
+template<class C>
+inline void Solver::printClause(const C& c)
+{
+    for (int i = 0; i < c.size(); i++){
+        printLit(c[i]);
+        fprintf(stderr, " ");
+    }
+}
+
+
+//=================================================================================================
+#endif
diff --git a/minisat/solver/SolverTypes.H b/minisat/solver/SolverTypes.H
new file mode 100644
index 0000000..f590f8e
--- /dev/null
+++ b/minisat/solver/SolverTypes.H
@@ -0,0 +1,201 @@
+/***********************************************************************************[SolverTypes.h]
+MiniSat -- Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
+associated documentation files (the "Software"), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge, publish, distribute,
+sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or
+substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
+NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
+OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+**************************************************************************************************/
+
+
+#ifndef SolverTypes_h
+#define SolverTypes_h
+
+#include <cassert>
+#include <stdint.h>
+
+//=================================================================================================
+// Variables, literals, lifted booleans, clauses:
+
+
+// NOTE! Variables are just integers. No abstraction here. They should be chosen from 0..N,
+// so that they can be used as array indices.
+
+typedef int Var;
+#define var_Undef (-1)
+
+
+class Lit {
+    int     x;
+ public:
+    Lit() : x(2*var_Undef)                                              { }   // (lit_Undef)
+    explicit Lit(Var var, bool sign = false) : x((var+var) + (int)sign) { }
+
+    // Don't use these for constructing/deconstructing literals. Use the normal constructors instead.
+    friend int  toInt       (Lit p);  // Guarantees small, positive integers suitable for array indexing.
+    friend Lit  toLit       (int i);  // Inverse of 'toInt()'
+    friend Lit  operator   ~(Lit p);
+    friend bool sign        (Lit p);
+    friend int  var         (Lit p);
+    friend Lit  unsign      (Lit p);
+    friend Lit  id          (Lit p, bool sgn);
+
+    bool operator == (Lit p) const { return x == p.x; }
+    bool operator != (Lit p) const { return x != p.x; }
+    bool operator <  (Lit p) const { return x < p.x;  } // '<' guarantees that p, ~p are adjacent in the ordering.
+};
+
+inline  int  toInt       (Lit p)           { return p.x; }
+inline  Lit  toLit       (int i)           { Lit p; p.x = i; return p; }
+inline  Lit  operator   ~(Lit p)           { Lit q; q.x = p.x ^ 1; return q; }
+inline  bool sign        (Lit p)           { return p.x & 1; }
+inline  int  var         (Lit p)           { return p.x >> 1; }
+inline  Lit  unsign      (Lit p)           { Lit q; q.x = p.x & ~1; return q; }
+inline  Lit  id          (Lit p, bool sgn) { Lit q; q.x = p.x ^ (int)sgn; return q; }
+
+const Lit lit_Undef(var_Undef, false);  // }- Useful special constants.
+const Lit lit_Error(var_Undef, true );  // }
+
+
+//=================================================================================================
+// Lifted booleans:
+
+
+class lbool {
+    char     value;
+    explicit lbool(int v) : value(v) { }
+
+public:
+    lbool()       : value(0) { }
+    lbool(bool x) : value((int)x*2-1) { }
+    int toInt(void) const { return value; }
+
+    bool  operator == (lbool b) const { return value == b.value; }
+    bool  operator != (lbool b) const { return value != b.value; }
+    lbool operator ^ (bool b) const { return b ? lbool(-value) : lbool(value); }
+
+    friend int   toInt  (lbool l);
+    friend lbool toLbool(int   v);
+};
+inline int   toInt  (lbool l) { return l.toInt(); }
+inline lbool toLbool(int   v) { return lbool(v);  }
+
+const lbool l_True  = toLbool( 1);
+const lbool l_False = toLbool(-1);
+const lbool l_Undef = toLbool( 0);
+
+//=================================================================================================
+// Clause -- a simple class for representing a clause:
+
+class Clause;
+
+template<class V>
+Clause* Clause_new(const V& ps, bool learnt = false);
+
+class Clause {
+    uint32_t size_etc;
+    union { float act; uint32_t abst; } extra;
+    Lit     data[0];
+
+public:
+    void calcAbstraction() {
+        uint32_t abstraction = 0;
+        for (int i = 0; i < size(); i++)
+            abstraction |= 1 << (var(data[i]) & 31);
+        extra.abst = abstraction;  }
+
+    // NOTE: This constructor cannot be used directly (doesn't allocate enough memory).
+    template<class V>
+    Clause(const V& ps, bool learnt) {
+        size_etc = (ps.size() << 3) | (uint32_t)learnt;
+        for (int i = 0; i < ps.size(); i++) data[i] = ps[i];
+        if (learnt) extra.act = 0; else calcAbstraction(); }
+
+    // -- use this function instead:
+    template<class V>
+    friend Clause* Clause_new(const V& ps, bool learnt) {
+        assert(sizeof(Lit)      == sizeof(uint32_t));
+        assert(sizeof(float)    == sizeof(uint32_t));
+        void* mem = malloc(sizeof(Clause) + sizeof(uint32_t)*(ps.size()));
+        return new (mem) Clause(ps, learnt); }
+
+    int          size        ()      const   { return size_etc >> 3; }
+    void         shrink      (int i)         { assert(i <= size()); size_etc = (((size_etc >> 3) - i) << 3) | (size_etc & 7); }
+    void         pop         ()              { shrink(1); }
+    bool         learnt      ()      const   { return size_etc & 1; }
+    uint32_t     mark        ()      const   { return (size_etc >> 1) & 3; }
+    void         mark        (uint32_t m)    { size_etc = (size_etc & ~6) | ((m & 3) << 1); }
+    const Lit&   last        ()      const   { return data[size()-1]; }
+
+    // NOTE: somewhat unsafe to change the clause in-place! Must manually call 'calcAbstraction' afterwards for
+    //       subsumption operations to behave correctly.
+    Lit&         operator [] (int i)         { return data[i]; }
+    Lit          operator [] (int i) const   { return data[i]; }
+    operator const Lit* (void) const         { return data; }
+
+    float&       activity    ()              { return extra.act; }
+    uint32_t     abstraction () const { return extra.abst; }
+
+    Lit          subsumes    (const Clause& other) const;
+    void         strengthen  (Lit p);
+};
+
+
+/*_________________________________________________________________________________________________
+|
+|  subsumes : (other : const Clause&)  ->  Lit
+|  
+|  Description:
+|       Checks if clause subsumes 'other', and at the same time, if it can be used to simplify 'other'
+|       by subsumption resolution.
+|  
+|    Result:
+|       lit_Error  - No subsumption or simplification
+|       lit_Undef  - Clause subsumes 'other'
+|       p          - The literal p can be deleted from 'other'
+|________________________________________________________________________________________________@*/
+inline Lit Clause::subsumes(const Clause& other) const
+{
+    if (other.size() < size() || (extra.abst & ~other.extra.abst) != 0)
+        return lit_Error;
+
+    Lit        ret = lit_Undef;
+    const Lit* c  = (const Lit*)(*this);
+    const Lit* d  = (const Lit*)other;
+
+    for (int i = 0; i < size(); i++) {
+        // search for c[i] or ~c[i]
+        for (int j = 0; j < other.size(); j++)
+            if (c[i] == d[j])
+                goto ok;
+            else if (ret == lit_Undef && c[i] == ~d[j]){
+                ret = c[i];
+                goto ok;
+            }
+
+        // did not find it
+        return lit_Error;
+    ok:;
+    }
+
+    return ret;
+}
+
+
+inline void Clause::strengthen(Lit p)
+{
+    remove(*this, p);
+    calcAbstraction();
+}
+
+#endif