#include <bits/stdc++.h>
 
using namespace std;
using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
 
mt19937 rng((int) chrono::steady_clock::now().time_since_epoch().count());
    
const int MOD = 998244353;
const int MAXN = 1e5 + 5;
const ll INF = 2e18;
 
int fexp(ll b, int e) {
    ll ans = 1;
    while (e) {
        if (e&1) ans = (ans * b) % MOD;
        b = (b * b) % MOD;
        e >>= 1;
    }
    return ans;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m;
    cin >> n >> m;
    cout << ((n - m + 1ll) * fexp(n + 1, m - 1)) % MOD << '\n';
    return 0;
}