#include <bits/stdc++.h>

using namespace std;

#define vec vector
#define ALL(x) (x).begin(), (x).end()
#define mp make_pair
#define mt make_tuple

typedef pair< int, int > pii;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

int const inf = 1000 * 1000 * 1000;
ll const inf64 = 1ll * inf * inf;


bool solve() {

    ll n, m;
    cin >> n >> m;

    cout << min(n - 1 + n * (m - 1), m - 1 + m * (n - 1)) << "\n";
    
    return true;
}

int main() {

#ifdef MY
    while(solve());
#else
    solve();
#endif

    return 0;
}