#include <iostream>
#include <fstream>
#include <vector>
#include <stack>
#include <chrono>
#include <iomanip>
#include <unordered_map>
#include <unordered_set>
#include <set>
#include <algorithm>
#include <thread>
#include <numeric>
#include <queue>
#include <functional>
#include <cmath>

using namespace std;

#define endl "\n"
#ifndef MAIN_BEGIN
#define START_TIMER(...)
#define TIMESTAMP(...)
#define MAIN_BEGIN int main() { \
    ios::sync_with_stdio(false);
#define RETURN return 0
#define MAIN_END RETURN; }
#define OUTPUT if(false) cout
#endif

MAIN_BEGIN

    long long n;
    long long m;
    cin >> n >> m;
    if(m > n) swap(m, n);
    cout << (m-1) + (n-1)*m;

MAIN_END