homework-00: Fix bad pointer comparison

homework-00-warmup/main.c

@@ -38,7 +38,7 @@ int main() {
 	// Check whether a range error occured or
 	// No characters were read by getline
 	// or check that strtol didnt move a single char
-	if(errno == ERANGE || chars_read == -1 || end == &buf[0]) {
+	if(errno == ERANGE || chars_read == -1 || end == buf) {
 		printf("%s\n", NOT_A_NUMBER);
 		return EXIT_FAILURE;
 	}