#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using ll = long long;
using ld = long double;
using mint = modint998244353;

int main() {
  int N, K; cin >> N >> K;
  mint ans = mint(K) * mint(K - 1) * mint(N) / mint(K).pow(N);
  cout << ans.val() << endl;
  return 0;
}