#include<bits/stdc++.h>
using namespace std;
typedef long long int ll;
const ll mod=998244353;
ll wer(int n, ll k) {
    ll x = 1;
    ll y = n % mod;
    while (k > 0) {
        if (k%2==1) {
            x = (x*y)%mod;
            k=k-1;
        }
        y=(y*y)%mod;
        k=k/2;
    }
    return x;
}

int main(){
	ll n,m;
	cin>>n>>m;
	cout<<wer(2,n*m-1)<<endl;
}