#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
const int mod = 998244353;
//using mint = modint1000000007;
//const int mod = 1000000007;
//const int INF = 1e9;
//const long long LINF = 1e18;
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep2(i,l,r)for(int i=(l);i<(r);++i)
#define rrep(i, n) for (int i = (n-1); i >= 0; --i)
#define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i)
#define all(x) (x).begin(),(x).end()
#define allR(x) (x).rbegin(),(x).rend()
#define P pair<int,int>
template<typename A, typename B> inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; }
template<typename A, typename B> inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; }
void calc(int n, int m, int k) {
	vector dp(m, vector<mint>(2));
	dp[0][0] = k;
	rep(i, m - 1) {
		dp[i + 1][0] += dp[i][1];
		dp[i + 1][1] += dp[i][0] * (k - 1);
		dp[i + 1][1] += dp[i][1] * (k - 2);
	}
	mint ans = dp[m - 1][1] * pow_mod(k - 1, n - m, mod);
	cout << ans.val() << endl;
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n, k; cin >> n >> k;
	dsu uf(n);
	vector<vector<int>>to(n);
	rep(i, n) {
		int a, b; cin >> a >> b;
		a--, b--;
		if (!uf.same(a, b)) {
			uf.merge(a, b);
		}
		else {
			vector<int>vec = { a };
			auto dfs = [&](auto self, int v, int p = -1)->bool {
				if (v == b)return true;
				for (auto nv : to[v]) {
					if (p == nv)continue;
					vec.push_back(nv);
					auto get = self(self, nv, v);
					if (get)return true;
					vec.pop_back();
				}
				return false;
			};
			dfs(dfs, a);
			int sz = vec.size();
			calc(n, sz, k);
			return 0;
		}
		to[a].push_back(b);
		to[b].push_back(a);
	}
	return 0;
}