#include<bits/stdc++.h>
using namespace std;
#define ll long long
map<pair<ll,ll>,ll > dp;
ll solve(ll n,ll m){
    if(n<=0 || m<=0)
        return 0;
    if(n==1 && m==1)
        return 0;
    if(dp.find(make_pair(n,m))!=dp.end())
       return dp[make_pair(n,m)];
    if(dp.find(make_pair(m,n))!=dp.end())
       return dp[make_pair(m,n)];
     return dp[make_pair(n,m)]=max(1+solve(n/2,m)+solve(n-(n/2),m),1+solve(n,m/2)+solve(n,m-(m/2)));
}
int main(){
    ll n,m,ans=0;cin >> n >> m ;
    cout<<solve(n,m)<<endl;
    return 0;
}