#include <bits/stdc++.h>   using namespace std;   int main() {     int n;     cin >> n;     vector<long long int> v, t;     v.push_back(0), t.push_back(0);     long long int sum = 0, tt = 1, x = 0;     double result = 0;     long long int ix, a, b;     for (int i = 0; i < n; ++i) {       cin >> ix;       if (ix == 1) {         cin >> a >> b;         t[a - 1] += b;         sum += a * b;       } else if (ix == 2) {         cin >> a;         v.push_back(a), t.push_back(0);         sum += a;         ++tt;       } else {         t[t.size() - 2] += t.back();         sum -= (v.back() + t.back());         --tt;         v.pop_back(), t.pop_back();       }       result = (double)sum / (double)tt;       cout << fixed << setprecision(6) << result <<   n ;     }   }   