import math

a, b = map(int, input().split())
D_2 = pow(a, 2) + pow(b, 2)
E_2 = pow(a, 2) - pow(b, 2)
F_2 = pow(b, 2) - pow(a, 2)
DEF = [D_2, E_2, F_2]
DEF_2 = []
i = 0
while i <= 2:
  if DEF[i] > 0:
    z = DEF[i]
    DEF_2.append(z)
  i += 1
ANS = min(DEF_2)
ans = math.sqrt(ANS)
print(ans)