题解 | #整数与IP地址间的转换#

#include <stdio.h>

int main() {
    int  ipin[4], ip_buf[12], g, s, b, i, j = 0;
    long long int anc = 0, exp = 1, ipd, mod;
    scanf("%d.%d.%d.%d", &ipin[3], &ipin[2], &ipin[1], &ipin[0]);
    scanf("%lld", &ipd);
    for (i = 0; i < 4; i++) {
        anc += ipin[i] * exp;
        exp = exp * 256;
    }
    printf("%lld\n", anc);
    i = 0;
    while (ipd > 256) {     //用while可以对更多位ip进行处理
        ip_buf[i] = ipd % 256;
        ipd = ipd / 256;
        i++;
    }
    ip_buf[i] = ipd;
    printf("%d.%d.%d.%d", ip_buf[3], ip_buf[2], ip_buf[1], ip_buf[0]);
    return 0;
}