import sys,random,bisect
from collections import deque,defaultdict
from heapq import heapify,heappop,heappush
from itertools import permutations
from math import log,gcd

input = lambda :sys.stdin.readline().rstrip()
mi = lambda :map(int,input().split())
li = lambda :list(mi())

X,Y = mi()

for Z in range(12):
    tmp = [X,Y,Z]
    tmp.sort()
    if tmp[1]-tmp[0]==4 and tmp[2]-tmp[1]==4:
        exit(print(Z))