from collections import *
from itertools import *
from functools import *
from heapq import *
import sys,math
input = sys.stdin.readline

a,b = map(int,input().split())

a,b = min(a,b),max(a,b)
if a==b:
    print(math.sqrt(a**2+b**2))
else:
    print(math.sqrt(b**2-a**2))