#include <stdio.h>
#include <algorithm>

typedef long long ll;

using namespace std;

int main() {
    ll n, m;
    scanf("%lld%lld", &n, &m);
    printf("%lld\n", min(m - 1 + m * (n - 1), n - 1 + n * (m - 1)));
    return 0;
}