A, B = map(int, input().split())
A %= 12

#tanshin = (A + (B/60))*30
#choshin = B*6
tanshin = 60*A + B
choshin = 12*B

diff = tanshin - choshin
if diff < 0:
    diff += 720

ans = (60*diff)//11
print(ans)