Arvonta

#include <cmath>
#include <iostream>
#include <vector>

using namespace std;

int main() {
    cin.sync_with_stdio(false);
    cin.tie(nullptr);

    int tc;
    cin >> tc;

    cout.precision(20);

    for(int ti = 0; ti < tc; ++ti) {
        int n;
        cin >> n;

        cout << 1.0 - std::pow(1.0 - 1.0 / (double)n, (double)n) << "\n";
    }

    return 0;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: ACCEPTED