# -*- coding: utf-8 -*-

N = int(input())
v = [int(a) for a in input().split()]

v.sort()

for i in range(N-1):
    tmp = (v[0]+v[1])/2
    v.pop(0)
    v.pop(0)
    v.insert(0,tmp)
    v.sort()
    print(v)

print(v[0])
