#include <bits/stdc++.h>   using namespace std;   int main() {     long long T, n;     cin >> T;     while (T--) {       cin >> n;       double x = (3.141592653589793238) / (2 * n);       cout << fixed << setprecision(10) << cos(x) / sin(x) <<   n ;     }     return 0;   }   