# coding: utf-8
import array, bisect, collections, copy, heapq, itertools, math, random, re, string, sys, time
sys.setrecursionlimit(10 ** 7)

from decimal import Decimal

INF = 10 ** 20
MOD = 10 ** 9 + 7


def II(): return int(input())
def ILI(): return list(map(int, input().split()))
def IAI(LINE): return [ILI() for __ in range(LINE)]
def IDI(): return {key: value for key, value in ILI()}


def read():
    a, b = ILI()
    return (a, b)


def solve(a, b):
    d_a = Decimal(a)
    d_b = Decimal(b)
    if d_a == d_b:
        ans = math.sqrt(d_a ** 2 + d_b ** 2)
    else:
        ans = math.sqrt(max(d_a, d_b) ** 2 - min(d_a, d_b) ** 2)
    return ans


def main():
    params = read()
    print(solve(*params))


if __name__ == "__main__":
    main()