1 files changed, 2 insertions, 0 deletions
diff --git a/puzzles.h b/puzzles.h
index de0f819..7b35896 100644
--- a/puzzles.h
+++ b/puzzles.h
@@ -12,6 +12,8 @@
 #define FALSE 0
 #endif
 
+#define PI 3.141592653589793238462643383279502884197169399
+
 #define lenof(array) ( sizeof(array) / sizeof(*(array)) )
 
 #define STR_INT(x) #x