#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <utility>
#include <cmath>
#include <queue>
#include <stack>
#include <map>
#include <set>
using namespace std;
#define lli long long int
#define M 1000000007
#define INF 1000000009
#define rep(i, a, b)  for (int i = int(a); i < int(b); i++)
#define nrep(i, a, b)  for (int i = int(a)-1; i >= int(b); i--)
#define sc(i) scanf("%d",&i)
#define di(i) printf("%d\n",i)
#define dii(i, j) printf("%d %d\n",i,j)
typedef vector <int> vi;
typedef pair <int,int> ii;
typedef vector <ii> vii;
typedef map <int,int> mi;
typedef map <ii,int> mii;

lli gcd(lli a,lli b) {
	if (b == 0) return a;
	return(a % b == 0 ? b : gcd(b, a % b)); 
}
int main() {
	lli n,m,mm,nn;
	cin >> n >> m;
    mm = max(m,n);
    nn = min(m,n);
	lli ans = (mm-1) + (nn-1)*mm;
	cout << ans << endl;
	return 0;
}