10970 - Big Chocolate（水题）

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll INF = 1000000000;
const int maxn = 100000+5;
int n,m;
int main() {
    while(~scanf("%d%d",&n,&m)) {
        printf("%d\n",n*(m-1) + n - 1);
    }
    return 0;
}