#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

long long int min(long long int a,long long int b)
{
    if(a>b)
        return b;
    else
        return a;
}
long long int max(long long int a,long long int b)
{
    if(a>b)
        return a;
    else
        return b;
}
int main() {

    /* Enter your code here. Read input from STDIN. Print output to STDOUT */ 
    long long int n,m,c,d,ans;
    scanf("%lld%lld",&n,&m);
    c=min(n,m);
    d=max(n,m);
    ans=(c-1)+c*(d-1);
    printf("%lld\n",ans);
    return 0;
}