#include <bits/stdc++.h>   using namespace std;   using ll = long long;   int main() {     int T;     cin >> T;     while (T--) {       int n;       cin >> n;       long double theta = 3.14159265358979323846 / (2 * n);       long double answer = 1 / tan(theta);       cout << setprecision(15) << answer <<   n ;     }     return 0;   }   