a,b,c = map(int,input().split())
if c < a:
    a,c = c,a

if a <= b <= c or a == c:
    print(0)
    exit()
    
ans = 10**20
for i in range(3):
    ans = min(ans,abs(a-b),abs(a-c))
    a,b,c = b,c,a
print(ans)