--- a/greedy.c
+++ b/greedy.c
@@ -13,6 +13,9 @@
 
 #include <ncurses.h>
 #include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <string.h>
 #include "playmodes.h"
 #include "playmodes.c"