1 files changed, 1 insertions, 0 deletions

diff --git a/ripser.cpp b/ripser.cpp
index 9fa2f3b..18c61c3 100644
--- a/ripser.cpp
+++ b/ripser.cpp
@@ -33,6 +33,7 @@
 #include <fstream>
 #include <cassert>
 #include <queue>
+#include <cmath>
 #include <unordered_map>
 
 #ifdef USE_GOOGLE_HASHMAP