import sys
pin=sys.stdin.readline
A,B=map(int,pin().split())
if A>=12:A-=12
t=A*3600+B*60
ans=3928
d=[3927*i+int(3*i/11) for i in range(12)]
for j in d:
  if j-t>=0:
    ans=min(ans,j-t)
print(ans)

#これAってまじ？