1

#include<bits/stdc++.h>
using namespace std;
int n, m, ans = 0;
int a[50], shift = 10;
void dfs(int d){
    ans=max(ans,d-2);
    if(d>m+n+2)
        return;
    for(int x=1;x<=d-1;x++){
        int y=d-x;
        if (x>n||y>m||a[x-y+20])
            continue;
        a[x-y+20]=1;
        dfs(d+1);
        a[x-y+20]=0;
    }
}
int main(){	
    cin>>n>>m;
    dfs(2);
    cout<<ans;
    return 0;
}