1 files changed, 1 insertions, 1 deletions
diff --git a/grid.c b/grid.c
index c2e08db..d2a3e13 100644
--- a/grid.c
+++ b/grid.c
@@ -13,7 +13,7 @@
 #include <ctype.h>
 #include <float.h>
 #include <limits.h>
-#include <math.h>
+#include <tgmath.h>
 
 #include "puzzles.h"
 #include "tree234.h"