A, B = gets.split.map(&:to_i)

c = Math.sqrt(A ** 2 + B ** 2)

if B > A
  d = Math.sqrt(B ** 2 - A ** 2)
  puts [c, d].min.round(12)
elsif B < A
  e = Math.sqrt(A ** 2 - B ** 2)
  puts [c, e].min.round(12)
else
  puts c.round(12)
end