Use strtol instead of checking each digit

This makes it both faster and smaller.

1 files changed, 1 insertions, 0 deletions

diff --git a/main.h b/main.h
index 61f7b1c..d6d758e 100644
--- a/main.h
+++ b/main.h
@@ -6,6 +6,7 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <stdlib.h>
 
 #include <assert.h>
 #include <string.h>