1 files changed, 4 insertions, 0 deletions
diff --git a/src/theory/arith/arith_utilities.h b/src/theory/arith/arith_utilities.h
index c764d0d2e..d50c48552 100644
--- a/src/theory/arith/arith_utilities.h
+++ b/src/theory/arith/arith_utilities.h
@@ -25,6 +25,7 @@
 #include "util/rational.h"
 #include "expr/node.h"
 #include "expr/attribute.h"
+#include <vector>
 #include <stdint.h>
 #include <limits>
 
@@ -55,6 +56,9 @@ inline void setArithVar(TNode x, ArithVar a){
   return x.setAttribute(ArithVarAttr(), (uint64_t)a);
 }
 
+typedef std::vector<uint64_t> ActivityMonitor;
+
+
 inline Node mkRationalNode(const Rational& q){
   return NodeManager::currentNM()->mkConst<Rational>(q);
 }