import sys
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#####################################################################

a, b = na()
for x in range(1, 10 ** 6):
    if x % a == b % x:
        print(x)
        exit()