結果
問題 | No.1392 Don't be together |
ユーザー |
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提出日時 | 2021-02-13 18:52:20 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 223 ms / 2,000 ms |
コード長 | 5,340 bytes |
コンパイル時間 | 2,098 ms |
コンパイル使用メモリ | 201,792 KB |
最終ジャッジ日時 | 2025-01-18 20:11:03 |
ジャッジサーバーID (参考情報) |
judge2 / judge5 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 27 |
ソースコード
#include <bits/stdc++.h>using namespace std;#define REP(i,n) for(ll i=0;i<(ll)n;i++)#define dump(x) cerr << "Line " << __LINE__ << ": " << #x << " = " << (x) << "\n";#define spa << " " <<#define fi first#define se second#define ALL(a) (a).begin(),(a).end()#define ALLR(a) (a).rbegin(),(a).rend()using ld = long double;using ll = long long;using ull = unsigned long long;using pii = pair<int, int>;using pll = pair<ll, ll>;using pdd = pair<ld, ld>;template<typename T> using V = vector<T>;template<typename T> using P = pair<T, T>;template<typename T> vector<T> make_vec(size_t n, T a) { return vector<T>(n, a); }template<typename... Ts> auto make_vec(size_t n, Ts... ts) { return vector<decltype(make_vec(ts...))>(n, make_vec(ts...)); }template<class S, class T> ostream& operator << (ostream& os, const pair<S, T> v){os << "(" << v.first << ", " << v.second << ")"; return os;}template<typename T> ostream& operator<<(ostream &os, const vector<T> &v) { for (auto &e : v) os << e << ' '; return os; }template<class T> ostream& operator<<(ostream& os, const vector<vector<T>> &v){ for(auto &e : v){os << e << "\n";} return os;}struct fast_ios { fast_ios(){ cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;template <class T> void UNIQUE(vector<T> &x) {sort(ALL(x));x.erase(unique(ALL(x)), x.end());}template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }void fail() { cout << -1 << '\n'; exit(0); }inline int popcount(const int x) { return __builtin_popcount(x); }inline int popcount(const ll x) { return __builtin_popcountll(x); }template<typename T> void debug(vector<vector<T>>&v,ll h,ll w){for(ll i=0;i<h;i++){cerr<<v[i][0];for(ll j=1;j<w;j++)cerr spa v[i][j];cerr<<"\n";}};template<typename T> void debug(vector<T>&v,ll n){if(n!=0)cerr<<v[0];for(ll i=1;i<n;i++)cerr spa v[i];cerr<<"\n";};const ll INF = (1ll<<62);// const ld EPS = 1e-10;// const ld PI = acos(-1.0);// const ll mod = (int)1e9 + 7;const ll mod = 998244353;template <std::uint_fast64_t Modulus> class modint {// long long から modint を作るときは必ず正の数にしてからコンストラクタに入れること!// そうしないとバグりますusing u64 = std::uint_fast64_t;public:u64 a;constexpr modint(const u64 x = 0) noexcept : a(x % Modulus) {}constexpr u64 &value() noexcept { return a; }constexpr const u64 &value() const noexcept { return a; }constexpr modint operator+(const modint rhs) const noexcept {return modint(*this) += rhs;}constexpr modint operator-(const modint rhs) const noexcept {return modint(*this) -= rhs;}constexpr modint operator*(const modint rhs) const noexcept {return modint(*this) *= rhs;}constexpr modint operator/(const modint rhs) const noexcept {return modint(*this) /= rhs;}constexpr modint &operator+=(const modint rhs) noexcept {a += rhs.a;if (a >= Modulus) {a -= Modulus;}return *this;}constexpr modint &operator-=(const modint rhs) noexcept {if (a < rhs.a) {a += Modulus;}a -= rhs.a;return *this;}constexpr modint &operator*=(const modint rhs) noexcept {a = a * rhs.a % Modulus;return *this;}constexpr modint &operator/=(modint rhs) noexcept {u64 exp = Modulus - 2;while (exp) {if (exp % 2) {*this *= rhs;}rhs *= rhs;exp /= 2;}return *this;}};using mint = modint<mod>;using vm = vector<mint>;using vvm = vector<vm>;ostream& operator << (ostream& os, const mint v){os << v.value(); return os;}template <class T, class U> constexpr T power(T x, U exp) {T ret = static_cast<T>(1);while (exp) {if (exp % static_cast<U>(2) == static_cast<U>(1))ret *= x;exp /= static_cast<U>(2);x *= x;}return ::std::move(ret);}int main(){// 二項係数const int n_max = 300000;std::vector<mint> fact(n_max);fact[0] = 1;for (int i = 1; i < n_max; ++i) {fact[i] = fact[i - 1] * i;}const auto comb = [&fact](int n, int r) {if(n<r or n<0 or r<0) return mint(0);return fact[n] / fact[r] / fact[n - r];};//ll N, M;cin >> N >> M;V<ll> P(N);REP(i, N) cin >> P[i], P[i]--;V<bool> visited(N, false);V<ll> lens;REP(i, N){if(visited[i]) continue;ll now = i;ll len = 0;while(1){if(visited[now]){lens.push_back(len);break;}visited[now] = true;len++;now = P[now];}}mint res = 0;mint kei = 1;mint minu = (-1+mod);REP(i, M+1){ll MA = 5050;ll k = M - i;V<mint> p(MA), q(MA);p[1] = k;q[1] = 0;REP(i, MA-1){if(i == 0) continue;p[i+1] = q[i];q[i+1] = p[i] * (k-1) + q[i] * (k-2);}mint tmp = 1;for(auto len: lens){tmp *= q[len];}res += kei * tmp * comb(M, i);kei *= minu;}cout << res/fact[M] << endl;return 0;}