/*
date:107/10/13
author:Chen Yi Jing

要將一堆圓圈塞進一個長方形裡，求最小長方形面積
1. 圓該怎麼擺
*/

#include <iostream>
#include <math.h>
using namespace std;
int main() {
    int line = 0, n = 0;

    while(cin >> line) {
        for (int i = 0; i < line; i++) {
            cin >> n;
            float num[n];
            for (int j = 0; j < n; j++) {
                cin >> num[j];
            }
            for (int j = 0; j < n; j++) {
                cout << num[j];
            }
        }
    }


    cout<< sqrt(1.5*1.5 - 0.5*0.5);
}