#include <algorithm>
#include <iostream>
#include <utility>
#include <vector>
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;

ll mod = 998244535;

int main() {
    ll X, Y;
    cin >> X >> Y;
    ll ans = 0;
    for (ll i = 1; i <= X; i++) {
        ans += 2 * max(X - 2 * i, 0LL) * Y;
        ans %= mod;
    }
    for (ll i = 1; i <= Y; i++) {
        ans += 2 * max(Y - 2 * i, 0LL) * X;
        ans %= mod;
    }
    cout << ans << endl;
}