#include <string.h>

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

	while (n--)
	{
		if (*a != *b)
			return *a - *b;
		a++;
		b++;
	}

	return 0;
}