#include <fstream>

using namespace std;

ifstream fin("buldo.in");
ofstream fout("buldo.out");
long long a, b, c, i, sol, n, s;
int main() {
    fin >> n;
    fin >> a;
    if (n == 1) {
        fout << a << "\n";
        return 0;
    }
    fin >> b;
    s = a;
    sol = a;
    s += b;
    sol = min(sol, s / 2);
    for (i = 3; i <= n; i++) {
        fin >> c;
        s += c;
        sol = min(sol, s / i);
        a = b;
        b = c;
    }
    fout << sol;
    return 0;
}