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#include <bits/stdc++.h>
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using namespace std;
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unsigned i, m, ip[4], ipmax[4], ipmin[4], mask[4];
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/**
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* 功能：比较器，四位，某一位有大小，就比如成功，小返回-1，大返回1，相等返回0
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* @param a
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* @param b
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* @return
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*/
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int cmp(unsigned *a, unsigned *b) {
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for (int i = 0; i < 4; ++i) {
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if (a[i] < b[i]) return -1;
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if (a[i] > b[i]) return 1;
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}
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return 0;
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}
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int main() {
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//输入几个IP地址
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while (scanf("%d", &m) != -1) {
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//读入第一次的ip地址
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scanf("%d.%d.%d.%d", &ip[0], &ip[1], &ip[2], &ip[3]);
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for (i = 0; i < 4; ++i) ipmax[i] = ipmin[i] = ip[i]; //初始化最大值与最小值
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//先减减，再循环，因为第一个读取过了
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while (--m) {
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scanf("%d.%d.%d.%d", &ip[0], &ip[1], &ip[2], &ip[3]);
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//如果比最大的大，那么替换掉最大的IP
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if (cmp(ip, ipmax) == 1)
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for (i = 0; i < 4; ++i) ipmax[i] = ip[i];
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else if (cmp(ip, ipmin) == -1) //如果比最小的小，那么替换掉最小的IP
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for (i = 0; i < 4; ++i) ipmin[i] = ip[i];
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}
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for (i = 0; i < 4; ++i) {
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// 原理： https://www.cnblogs.com/xienaoban/p/6798101.html
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if (i == 0 || mask[i - 1] == 255) {
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//最大最小两个ip进行异或运算，目的是找出第一个开始不一样的地方，然后再与1111 1111（二进制，即255）异或运算，
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// 相当于取反，但是这里不能直接使用取反运算“~”
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mask[i] = 255 ^ (ipmax[i] ^ ipmin[i]);
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//因为一个unsigned有32位，会使得比1111 1111高位的0也取反。于是得到子网掩码的雏形。
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// 而子网掩码前n位连续为1，后32-n位连续为0，这个雏形仅仅办到了前n位为1，所以得想办法把后32-n位清零
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for (int j = 0; j <= 8; ++j)
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if ((mask[i] >> j) == (255 >> j)) {
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mask[i] = ((mask[i] >> j) << j);
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break;
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}
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} else { mask[i] = 0; }
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}
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printf("%u.%u.%u.%u\n", mask[0] & ipmax[0], mask[1] & ipmax[1], mask[2] & ipmax[2], mask[3] & ipmax[3]);
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printf("%u.%u.%u.%u\n", mask[0], mask[1], mask[2], mask[3]);
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}
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return 0;
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}
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