diff --git a/a1/program.c b/a1/program.c
index 1797138..6e5458f 100644
--- a/a1/program.c
+++ b/a1/program.c
@@ -14,7 +14,7 @@ void caps() {
 		char out = '\0';
 		if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')) {
 			out = (c < 'a') ? c + 'a'-'A' : (c - ('a' - 'A'));
-		} else {
+		} else if (c >= 32 && c <= 126){
 			out = c;
 		}
 	putchar(out);