<filename>submissions/abc138/c.py
import sys
input = sys.stdin.readline

n = int(input())
v = list(map(int, input().split()))
v.sort()
for i in range(n-1):
    v[i+1] = (v[i]+v[i+1])/2
print(v[n-1])

<filename>submissions/abc138/c.py
import sys
input = sys.stdin.readline

n = int(input())
v = list(map(int, input().split()))
v.sort()
for i in range(n-1):
    v[i+1] = (v[i]+v[i+1])/2
print(v[n-1])
