import math
s = input().split()
a = float(s[0])
b = float(s[1])
c1 = 0.0
c2 = 0.0

c1 = a * a + b * b
c1 = math.sqrt(c1)

if a != b:
    c2 = math.fabs(b * b - a * a)
    c2 = math.sqrt(c2)

if c2 == 0.0:
    print(c1)
else:
    print(min(c1,c2))