#include <bits/stdc++.h>
using namespace std;


const int mod = 998244353;

int modmul(int64_t a, int64_t b) {
    return a * b % mod;
}

int modadd(int a, int b) {
    return (a + b) % mod;
}
int modsub(int a, int b) {
    return (a - b + mod) % mod;
}

int modpow(int a, int b) {
    int r = 1;
    while (b) {
        if (b & 1) {
            r = modmul(r , a);
        }
        a = modmul(a, a);
        b >>= 1;
    }
    return r;
}


int C(int64_t a, int b) {
    assert (b == 4);

    int res = 1;
    for (int j = 0; j < 4; j++)
        res = modmul(res, a - j);
    return modmul(res, modpow(24, mod - 2));
}

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int64_t H, W;
    cin >> H >> W;
    
    int ans = 0;

    ans = modadd(ans, modmul(11, modmul(C(H, 4), C(W, 4))));

    ans = modadd(ans, modmul(C(H, 4), modmul(modmul(W-1,W-1), W)));
    ans = modadd(ans, modmul(C(W, 4), modmul(modmul(H-1,H-1), H)));

    ans = modsub(ans, modmul(C(H, 4), 1LL*W*(W-1)/2%mod));
    ans = modsub(ans, modmul(C(W, 4), 1LL*H*(H-1)/2%mod));
    cout << ans << '\n';

    return 0;
}