int tou, jiao, tu_tou, ji_tou;

cout << "请输入鸡和兔的头总数：";
cin >> tou;
cout << "请输入鸡和兔的脚总数：";
cin >> jiao;

for (tu_tou = 0; tu_tou < tou + 1; tu_tou++) {
    ji_tou = tou - tu_tou;
    if (tu_tou * 4 + ji_tou * 2 == jiao)
        printf("兔的数量=%d,鸡的数量=%d\n", tu_tou, ji_tou);
}
if (tu_tou == tou)
    printf("无解\n");