HDU 1238 Substring

#include <iostream>#include <string>#include <algorithm>using namespace std;int main(){int t, n, i;cin >> t;while(t--){string s[101];cin >> n; int len = 1000, j = 0, max, f = 0;for(i = 0; i < n; i++){cin >> s[i];if(s[i].size() < len){len = s[i].size();j = i;}}max = len;string str;str = s[0];s[0] = s[j];s[j] = str;while(len){for(i = 0; i + len <= max; i++){str = s[0].substr(i, len);for(j = 1; j < n; j++)if(s[j].find(str) == -1)break;if(j == n){f = 1;break;}char t;for(j = 0; j < len / 2; j++){t = str[j];str[j] = str[len - 1 - j];str[len - 1 -j] = t;}for(j = 1; j <=n; j++)if(s[j].find(str) == -1)break;if(j == n){f = 1;break;}}if(f)break;len--;}cout << len << endl;}return 0;}