# coding: utf-8
# Your code here!
import sys
readline = sys.stdin.readline
read = sys.stdin.read

a,b = [int(i) for i in readline().split()]

ans = 0
if b > a: a,b = b,a
a -= 1
while True:
    if ans&1==0:
        if b==0: break
        b -= 1
    else:
        if a==0: break
        a -= 1
    ans += 1
        
print(ans)