#!/usr/bin/env python

S = map(int,raw_input().split())
SL = len(S)

max = 0
min =101
for i in range(0,SL):
     if S[i] > max:
          max = S[i]
     if S[i] < min :
          min = S[i]

calc = 0
for i in range(0,SL):
     if S[i] != max and S[i] != min:
          calc = calc + S[i]

calc2 = float(calc) / (SL - 2)
print calc2