diff --git a/main.cpp b/main.cpp
index 9b98031..93e91d5 100644
--- a/main.cpp
+++ b/main.cpp
@@ -14,6 +14,7 @@
 
 
 #include <iostream>
+#define _USE_MATH_DEFINES
 #include <cmath>
 #include <cstring>
 #include <ctime>