The input contains between 1 and 10 lines, *i*-th line contains an integer number *x*<sub class="lower-index">*i*</sub> (0 ≤ *x*<sub class="lower-index">*i*</sub> ≤ 9).
foo, bar, baz, quz = [0, 0, 0, 1]
tux = int(input())
for _ in range(tux):
        pur = int(input())
        foo += pur
        bar += 1
        if foo * quz > bar * baz:
                baz = foo
                quz = bar
print(baz / quz)