p=998244353
H,W=map(int,input().split())
ans=H*W*(H*W-1)
#右下にいると仮定
nH=H//2
nW=W//2
sub=(1+nH)*nH//2*(1+nW)*nW//2*4
if H%2==1:
    sub+=W*(H-1)
else:
    sub+=W*2*(H-1)
if W%2==1:
    sub+=H*(W-1)
else:
    sub+=H*2*(W-1)
print((ans-sub)%p)