make var-queue a template

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

Author: NikolajBjorner

src/sat/sat_solver.h

@@ -164,7 +164,7 @@ namespace sat {
         unsigned                m_rephase_inc;
         backoff                 m_rephase;
         backoff                 m_reorder;
-        var_queue               m_case_split_queue;
+        var_queue<unsigned_vector> m_case_split_queue;
         unsigned                m_qhead;
         unsigned                m_scope_lvl;
         unsigned                m_search_lvl;

src/util/var_queue.h

@@ -21,20 +21,20 @@ Revision History:
 #include "util/heap.h"
 
 
-    
+template <class ActivityVector>    
 class var_queue {
     typedef unsigned var;
 
     struct lt {
-        svector<unsigned> & m_activity;
-    lt(svector<unsigned> & act):m_activity(act) {}
+        ActivityVector & m_activity;
+        lt(ActivityVector & act):m_activity(act) {}
         bool operator()(var v1, var v2) const { return m_activity[v1] > m_activity[v2]; }
     };
     heap<lt>  m_queue;
-public:
 
+public:
 
-    var_queue(svector<unsigned> & act):m_queue(128, lt(act)) {}
+    var_queue(ActivityVector & act):m_queue(128, lt(act)) {}
 
     void activity_increased_eh(var v) {
         if (m_queue.contains(v))
@@ -90,11 +90,12 @@ class var_queue {
         return out;
     }
 
-    using const_iterator = decltype(m_queue)::const_iterator;
+    using const_iterator = const int *;
     const_iterator begin() const { return m_queue.begin(); }
     const_iterator end() const { return m_queue.end(); }
 };
 
-inline std::ostream& operator<<(std::ostream& out, var_queue const& queue) {
+template <typename T>
+inline std::ostream& operator<<(std::ostream& out, var_queue<T> const& queue) {
     return queue.display(out);
 }