From 493090894237037758b8fa066466e8797fd40656 Mon Sep 17 00:00:00 2001
From: Sebastian Junges <sebastian.junges@gmail.com>
Date: Thu, 23 Apr 2020 15:57:16 -0700
Subject: [PATCH] new version of containsVariable, with better performance and
 somewhat better to debug

---
 src/storm/storage/expressions/Expression.cpp | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/storm/storage/expressions/Expression.cpp b/src/storm/storage/expressions/Expression.cpp
index 0221628db..520bf1db4 100644
--- a/src/storm/storage/expressions/Expression.cpp
+++ b/src/storm/storage/expressions/Expression.cpp
@@ -133,9 +133,12 @@ namespace storm {
         
         bool Expression::containsVariable(std::set<storm::expressions::Variable> const& variables) const {
             std::set<storm::expressions::Variable> appearingVariables = this->getVariables();
-            std::set<storm::expressions::Variable> intersection;
-            std::set_intersection(variables.begin(), variables.end(), appearingVariables.begin(), appearingVariables.end(), std::inserter(intersection, intersection.begin()));
-            return !intersection.empty();
+            for (auto const& v : variables) {
+                if (appearingVariables.count(v) > 0) {
+                    return true;
+                }
+            }
+            return false;
         }
 
         bool Expression::containsVariableInITEGuard(std::set<storm::expressions::Variable> const& variables) const {