#include <stdio.h>

int main () {
  int n = 0;
  long long h = 0LL;
  long long w = 0LL;
  
  int res = 0;
  
  long long ans = 0LL;
  long long mod_num = 998244353LL;
  
  long long tmp = 0LL;
  
  res = scanf("%lld", &h);
  res = scanf("%lld", &w);
  
  ans = (h*w)%mod_num;
  ans = (ans*ans)%mod_num;
  ans += mod_num-(h*w)%mod_num;
  
  tmp = ((1+h/2LL)*(h/2LL))%mod_num;
  tmp *= w;
  tmp %= mod_num;
  ans += mod_num-tmp%mod_num;
  
  tmp = ((1+w/2LL)*(w/2LL))%mod_num;
  tmp *= h;
  tmp %= mod_num;
  ans += mod_num-tmp%mod_num;
  
  tmp = ((1+h/2LL)*(h/2LL))%mod_num;
  tmp *= ((1+w/2LL)*(w/2LL))%mod_num;
  tmp %= mod_num;
  
  ans += mod_num-tmp;
  
  printf("%lld\n", ans%mod_num);
  return 0;
}