A, B = gets.split.map(&:to_i)
T = 60 * 60 * 24

def f(t)
  t * Rational(360, 60 * 60)
end

def g(t)
  t * Rational(360, 60 * 60 * 12)
end

def t1(m, s)
  (m * 60 + s) % 3600
end

def t2(h, m, s)
  ((h * 60 * 60) + m * 60 + s) % (60 * 60 * 12)
end

0.upto(7200) do |i|
  a = f(t1(B, i))
  b = g(t2(A, B, i))
  c = f(t1(B, i + 1))
  d = g(t2(A, B, i))

  if a <= b && c >= d
    puts i
    exit
  end
end