#include<bits/stdc++.h>
#include<atcoder/all>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<vector<int>> vvi;
typedef vector<vector<long long>> vvl;
typedef long double ld;
typedef pair<int, int> P;

ostream& operator<<(ostream& os, const modint& a) {os << a.val(); return os;}
template <int m> ostream& operator<<(ostream& os, const static_modint<m>& a) {os << a.val(); return os;}
template<typename T> istream& operator>>(istream& is, vector<T>& v){int n = v.size(); assert(n > 0); rep(i, n) is >> v[i]; return is;}
template<typename U, typename T> ostream& operator<<(ostream& os, const pair<U, T>& p){os << p.first << ' ' << p.second << "\n"; return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : " "); return os;}
template <typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v){int n = v.size(); rep(i, n) os << v[i] << (i == n - 1 ? "\n" : ""); return os;}

using mint = modint998244353;

int main(){
	int n, k;
	cin >> n >> k;
	vvi G(n);
	rep(i, n){
		int u, v;
		cin >> u >> v;
		u--; v--;
		G[u].push_back(v);
		G[v].push_back(u);
	}
	int start = -1;
	int end = -1;
	vector<int> p(n, -1);
	auto dfs = [&](int from, int prev, auto dfs) -> void{
		for(int to : G[from]){
			if(start != -1) continue;
			if(to == prev) continue;
			if(p[to] != -1){
				start = from;
				end = to;
				return;
			}
			p[to] = from;
			dfs(to, from, dfs);
		}
	};
	p[0] = -2;
	dfs(0, -1, dfs);
//	cout << p;
//	cout << start << ' ' << end << "\n";
	vi loop;
	{
		int from = start;
		while(true){
			loop.push_back(from);
			if(from == end) break;
			from = p[from];
		}
	}
//	cout << loop;
	int m = loop.size();
	mint ans = 1;
	vector<mint> same(m), dif(m);
	same[0] = k;
	rep(i, m - 1){
		dif[i + 1] = same[i] * (k - 1) + dif[i] * (k - 2);
		same[i + 1] = dif[i];
	}
	ans *= dif[m - 1];
	ans *= mint(k - 1).pow(n - m);
	cout << ans;
	return 0;
}