import sys
input=sys.stdin.readline
def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))

def main():
    mod=10**9+7
    L=LI()
    L.sort()
    
    d1=L[1]-L[0]
    d2=L[2]-L[1]
    
    print(min(d1,d2))
        
        


main()