#include <bits/stdc++.h>   using namespace std;   int main() {     int tux;     cin >> tux;     int foo, bar, baz, quz, pur, oo;     foo = bar = baz = 0;     quz = 1;     while (tux) {       cin >> pur;       foo += pur;       bar++;       if (foo * quz > bar * baz) {         baz = foo;         quz = bar;       }       tux--;     }     cout.precision(5);     cout << fixed << (baz * 1. / quz);     return 0;   }   