#include <stddef.h>

int memcmp(const void *a, const void *b, size_t n)
{
    const unsigned char *s1 = a, *s2 = b;

    for (size_t i = 0; i < n; i++) {
        if (s1[i] != s2[i]) {
            return ((s1[i] < s2[i]) ? -1 : 1);
        }
    }

    return 0;
}