C++程序  |  22行  |  355 B

/*
 * strncmp.c
 */

#include <string.h>

int strncmp(const char *s1, const char *s2, size_t n)
{
    const unsigned char *c1 = (const unsigned char *)s1;
    const unsigned char *c2 = (const unsigned char *)s2;
    unsigned char ch;
    int d = 0;

    while (n--) {
	d = (int)(ch = *c1++) - (int)*c2++;
	if (d || !ch)
	    break;
    }

    return d;
}