#include <stdio.h>

int str_cmp(char *s, char *t)
{
	while (*s == *t) {
		if (*s == '\0')
			return 0;
		else {
			s++; t++;
		}
	}
	return *s - *t;
}

main()
{
	char s[] = "apple";
	char t[] = "appel";

	printf("strcmp(s, t) = %d\n", str_cmp(s, t));
}