XDU 1010

蛋疼的格式要求，，恨一切输出格式要求！！！！！！

#include <iostream>using namespace std;int vis[21];int n;int answer[21];int casenum;bool isprime(int temp){for(int i = 2; i*i <= temp; i++)if(temp % i == 0)return false;return true;}void answerout(){cout << endl; cout << answer[0];for(int i = 1; i < n; i++)cout << " " << answer[i];}void dfs(int c){if(c == n){if(isprime(answer[c-1] + 1))answerout();return;}for(int i = 1; i <= n; i++){if(!vis[i] && isprime(i + answer[c-1])){vis[i] = 1;answer[c] = i;dfs(c+1);vis[i] = 0;}}}int main(){while(cin >> n){casenum++;if(casenum != 1){cout << endl;}cout << "Case " << casenum << ":";answer[0] = 1;vis[1] = 1;dfs(1);cout << endl;}return 0;}