#include <bits/stdc++.h>
#define Fst first
#define Snd second
#define MP make_pair
#define ll long long
#define PII pair<int,int>
#define PIL pair<int,ll>
#define PLI pair<ll,int>
#define PLL pair<ll,ll>
#define PDD pair<double,double>
using namespace std;
ll n,m,md=998244353;
inline ll ksm(ll x,ll y)
{
    ll r=1; for (int i=0;i<35;i++,x=(x*x)%md) if (y&(1ll<<i)) r=(r*x)%md;
    return r;
}
inline ll rev(ll x)
{
    return ksm(x,md-2);
}
inline ll C(ll al,ll sm)
{
    ll r=1; for (ll i=al;i>al-sm;i--) r=(r*i)%md;
    for (ll i=1;i<=sm;i++) r=(r*rev(i))%md;
    return r;
}
int main()
{
    scanf("%lld%lld",&n,&m);
    ll res=(C(n,4)*ksm(C(m,2),2))%md;
    //cerr <<res<<" res\n";
    res+=(C(m,4)*ksm(C(n,2),2))%md;
    //cerr <<res<<" res\n";
    res-=(C(n,4)*C(m,4))%md;
    //cerr <<res<<" res\n";
    res=(res%md+md)%md;
    //cerr <<res<<" res\n";
    printf("%lld\n",res); return 0;
}