import sys
input=sys.stdin.readline
def I(): return int(input())
def MI(): return map(int, input().split())
def LI(): return list(map(int, input().split()))

def main():
    mod=10**9+7
    A,B=MI()
    a=30*A+0.5*B
    b=6*B
    if a<b:
        a+=360
    d=a-b
    
    if d==360:
        print(0)
        exit()
    t=(d*60)/5.5
    print(int(t))


main()