#include<iostream> using namespace std; const int maxn = 1010; double ans[maxn] = { 0 }; void init() { double sum = 0; for (int i = 1;i <= maxn;i++) { if (i % 2 == 1) { sum += 1.0 / i; } else { sum -= 1.0 / i; } ans[i] = sum; } } int main() { init(); int m, n; cin >> m; for (int i = 0;i < m;i++) { cin >> n; printf("%.2f\n", ans[n]); } return 0; }