#include <bits/stdc++.h>
using namespace std;
#define int long long
#define db double
#define gcd(a,b) __gcd(a,b)
#define lcm(a,b) a*b / __gcd(a,b)
#define I first
#define II second
#define pb push_back
#define ii pair<int,int>
const int INF = 2 * 1e9;
const int N = 2e5 + 1;
const int MOD = 998244353;
int pw(int a, int b) {
    int res = 1;
    while (b) {
        if (b & 1) res = (res * a) % MOD;
        b /= 2;
        a = (a * a) % MOD;
    }
    return res;
}
int32_t main()
{
    #define TASKNAME "test"
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if (fopen(TASKNAME ".inp","r" ))
    {
        freopen(TASKNAME ".inp","r",stdin);
        freopen(TASKNAME ".out","w",stdout);
    }
    int h, w;
    cin >> h >> w;
    cout << pw(2, (h - 1) * (w - 1) + 2);
    return 0;
}