# coding: utf-8
# Your code here!
import sys
sys.setrecursionlimit(10**6)
readline = sys.stdin.readline
read = sys.stdin.read

import datetime

#n = int(input())
#n,k = [int(i) for i in readline().split()]
#a = [int(i) for i in readline().split()]

abc = [int(i) for i in input().split()]
s = sorted(abc)

ans = min(s[1]-s[0],s[2]-s[1])

if abc[1] == s[1]: ans = 0

print(ans)