diff --git a/tutorial/703_Decimation/main.cpp b/tutorial/703_Decimation/main.cpp
index c299ccf7f..0aecbb50b 100755
--- a/tutorial/703_Decimation/main.cpp
+++ b/tutorial/703_Decimation/main.cpp
@@ -67,6 +67,7 @@ int main(int argc, char * argv[])
 
     C.resize(E.rows(),V.cols());
     VectorXd costs(E.rows());
+    Q.clear();
     for(int e = 0;e<E.rows();e++)
     {
       double cost = e;