#include #include using namespace std; // using mint = long double; // using mint = modint998244353; // using mint = modint1000000007; typedef long long ll; typedef pair P; typedef pair T; typedef pair > Pd; const ll INF = 1e18; const ll fact_table = 3200008; priority_queue pql; priority_queue

pqp; //big priority queue // priority_queue , greater > pqls; priority_queue , greater

> pqps; //small priority queue //top pop ll dx[8] = {1, 0, -1, 0, 1, 1, -1, -1}; ll dy[8] = {0, 1, 0, -1, -1, 1, 1, -1}; //↓,→,↑,← /* #define endl "\n" #ifdef ENJAPMA #undef endl #endif */ #define p(x) cout<= (b); i--) typedef vector vec; typedef vector> mat; // vec v(n) -> 長さnのベクトルを宣言 // mat dp(h, vec(w)) -> h * w の行列を宣言 const ll mod = 998244353ll; // const ll mod = 1000000007ll; ll mypow(ll a, ll b, ll m = mod) {ll x = 1; while (b) {while (!(b & 1)) {(a *= a) %= m; b >>= 1;}(x *= a) %= m; b--;} return x;} vec rv(ll read) { vec res(read); for (int i = 0; i < read; i++) { cin >> res[i]; } return res;} void YES(bool cond) { if (cond) { p("YES");} else { p("NO");} return;} void Yes(bool cond) { if (cond) { p("Yes");} else { p("No");} return;} void line() { p("--------------------"); return;} ll fact[fact_table + 5], rfact[fact_table + 5]; void c3_init() { fact[0] = rfact[0] = 1; for (ll i = 1; i <= fact_table; i++) { fact[i] = (fact[i - 1] * i) % mod; } rfact[fact_table] = mypow(fact[fact_table], mod - 2, mod); for (ll i = fact_table; i >= 1; i--) { rfact[i - 1] = rfact[i] * i; rfact[i - 1] %= mod; } return; } ll c3(ll n, ll r) { return (((fact[n] * rfact[r]) % mod ) * rfact[n - r]) % mod; } bool icpc = false; bool multicase = false; ll n, m; ll p[5005]; ll x[5005]; bool used[5005][5005]; ll dp[5005][5005][3]; ll dfs(ll color, ll i, ll par) { if (used[color][i]) { // 清算を行う return dp[color][par][0]; } used[color][i] = true; if (par == -1) { dp[color][i][0] = 0; dp[color][i][1] = color; } else { dp[color][i][1] += dp[color][par][0]; dp[color][i][0] += dp[color][par][1] * (color - 1) % mod; dp[color][i][0] += dp[color][par][0] * (color - 2) % mod; dp[color][i][0] %= mod; } return dfs(color, p[i], i); } bool solve() { cin >> n >> m; c3_init(); for (int i = 1; i <= n; i++) { cin >> p[i]; } for (int color = 1; color <= m; color ++) { ll res = 1ll; for (int i = 1; i <= n; i++) { if (!used[color][i]) { res *= dfs(color, i, -1); res %= mod; } } x[color] = res; } ll ans = 0ll; ll flag = 1ll; for (int color = m; color >= 1; color --) { ans += ((x[color] * flag) % mod) * c3(m, color) % mod; flag = (mod - flag); ans %= mod; } ans *= rfact[m]; ans %= mod; p(ans); return true; } int main() { ios::sync_with_stdio(false); cin.tie(nullptr); if (icpc) { while (solve()); return 0; } ll q, testcase = 1; if (multicase) { cin >> q; } else { q = 1; } while (q--) { // pu("Case ");pu("#");pu(testcase);pu(": "); solve(); testcase++; } // solve(); return 0; }