#include<bits/stdc++.h>
#define L(i, j, k) for(int i = (j); i <= (k); ++i)
#define R(i, j, k) for(int i = (j); i >= (k); --i)
#define ll long long
#define sz(a) ((int) (a).size())
#define vi vector < int > 
#define me(a, x) memset(a, x, sizeof(a))
#define ull unsigned long long
#define ld __float128
using namespace std;
const int N = 3e5 + 7, mod = 998244353;
int qpow(int x, int y = mod - 2) {
	int res = 1;
	for(; y; x = (ll) x * x % mod, y >>= 1) if(y & 1) res = (ll) res * x % mod;
	return res;
}
int n, m;
inline int C(int n, int k) {
	int prd = 1;
	L(i, 0, k - 1) prd = (ll) prd * (n - i) % mod;
	L(i, 1, k) prd = (ll) prd * qpow(i) % mod;
	return prd;
}
int main() {
	ios :: sync_with_stdio(false);
	cin.tie(0); cout.tie(0);
	cin >> n >> m; 
	int ns = 0;
	(ns += (ll) C(n, 4) * C(m, 2) % mod * C(m, 2) % mod) %= mod;
	(ns += (ll) C(m, 4) * C(n, 2) % mod * C(n, 2) % mod) %= mod;
	(ns += mod - (ll) C(n, 4) * C(m, 4) % mod) %= mod;
	cout << ns << '\n';
	return 0;
}