#include <bits/stdc++.h>

#include <atcoder/modint>
using namespace std;
using mint = atcoder::modint998244353;
void fast_io() {
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
}

int main() {
    fast_io();
    int n, k;
    cin >> n >> k;
    vector<vector<int>> g(n);
    vector<int> deg(n, 0);
    for (int i = 0; i < n; i++) {
        int u, v;
        cin >> u >> v;
        u--, v--;
        g[u].push_back(v);
        g[v].push_back(u);
        deg[u]++;
        deg[v]++;
    }
    deque<int> q;
    for (int i = 0; i < n; i++) {
        if (deg[i] == 1) {
            q.push_back(i);
        }
    }
    while (!q.empty()) {
        int u = q.front();
        q.pop_front();
        for (int v : g[u]) {
            if (deg[v] > 1) {
                deg[v]--;
                if (deg[v] == 1) {
                    q.push_back(v);
                }
            }
        }
    }
    int loop = 0;
    for (int i = 0; i < n; i++) {
        if (deg[i] > 1) {
            loop++;
            assert(deg[i] == 2);
        }
    }
    mint ans = mint(k - 1).pow(loop) + (loop % 2 ? -(k - 1) : k - 1);
    ans *= mint(k - 1).pow(n - loop);
    cout << ans.val() << endl;
}