#include <iostream>
#include <fstream>
#include <vector>
#include <stack>
#include <algorithm>
#include <queue>
#include <string>
#include <cmath>
#include <map>
#include <set>
#include <cassert>
#define MOD 1e9 + 7
#define eps 1e-9
#define pb push_back
#define mp make_pair
#define ft first
#define sd second
#define sz(a) a.size()
#define loop(i, n) for(long long (i) = 0; (i) < (n) ; ++ (i))
#define loopn()
#define pii pair<int,int>
#define pll pair<long long,long long>
#define vii vector<int>
#define vll vector<long long>  
typedef long long ll;
typedef long double ld;

using namespace std;


/*@Sergey_Miller*/


ll f(ll n, ll m) {
    if(n == 1) {
        return m-1;
    }
    if(m == 1) {
        return n-1;
    }
    if(n < m) {
        swap(n,m);
    }
    ll ans = n;
    if(m%2 == 0) {
        return 1 + 2*f(n,m/2);
    } else {
        return 1 + f(n,m/2) + f(n,m/2  +1);
    }
}


void solve() {
    ll n,m;
    cin >> n >> m;
    cout << f(n,m);
}

int main () {
    ios::sync_with_stdio(false);
     // freopen("input.txt", "r", stdin);
 //  freopen("output.txt", "w", stdout);
    solve();
    return 0;
}