#include <iostream>
#include <cmath>
#include <cstdio>
#include <set>
#include <algorithm>
#include <vector>
#include <map>
#include <cassert>
#include <string>
#include <cstring>
#include <queue>

using namespace std;
#define rep(i,a,b) for(int i=a;i<b;i++)
#define S(x) scanf("%d",&x)
#define S2(x,y) scanf("%d%d",&x,&y)
#define P(x) printf("%d/n",x)
#define all(v) v.begin(),v.end()

typedef long long int ll;
typedef pair<int,int>pii;
typedef vector<int> vi;
int main()
{
        long long int n,m;
        cin>>n>>m;
        long long int x,y;
        x=max(n,m);
        y=min(n,m);
        cout<<x-1+x*(y-1)<<endl;
        return 0;
}