제출 #540860

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
540860		Bungmint	Amusement Park (CEOI19_amusementpark)	C++17	100 / 100	1534 ms	1712 KiB

amusementpark

//Copyright © 2022 Youngmin Park. All rights reserved.
#pragma GCC optimize("O3")
#pragma GCC target("avx2")
#include <bits/stdc++.h>
using namespace std;

using ll = long long;
using vi = vector<int>;
using pii = pair<int, int>;
using vpi = vector<pii>;
using pll = pair<ll, ll>;
using vl = vector<ll>;
using vpl = vector<pll>;
using ld = long double;
template <typename T, size_t SZ>
using ar = array<T, SZ>;

#define all(v) (v).begin(), (v).end()
#define pb push_back
#define sz(x) (int)(x).size()
#define fi first
#define se second
#define lb lower_bound
#define ub upper_bound
#define FOR(i, a, b) for (int i = (a); i < (b); ++i)
#define F0R(i, a) FOR(i, 0, a)
#define ROF(i, a, b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i, a) ROF(i, 0, a)
#define REP(a) F0R(_, a)

const int INF = 1e9;
const ll LINF = 1e18;
const int MOD = 998244353;
const ld PI = acos((ld)-1.0);
const int dx[4] = {1, 0, -1, 0}, dy[4] = {0, 1, 0, -1};
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T>
using pqg = priority_queue<T, vector<T>, greater<T>>;
template <typename T>
bool ckmin(T &a, const T &b) { return b < a ? a = b, 1 : 0; }
template <typename T>
bool ckmax(T &a, const T &b) { return b > a ? a = b, 1 : 0; }

template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p)
{
    return os << '(' << p.first << ", " << p.second << ')';
}
template <typename T_container, typename T = typename enable_if<!is_same<T_container, string>::value, typename T_container::value_type>::type>
ostream &operator<<(ostream &os, const T_container &v)
{
    os << '{';
    string sep;
    for (const T &x : v)
        os << sep << x, sep = ", ";
    return os << '}';
}
void dbg_out()
{
    cerr << endl;
}
template <typename Head, typename... Tail>
void dbg_out(Head H, Tail... T)
{
    cerr << ' ' << H;
    dbg_out(T...);
}
#ifdef LOCAL
#define dbg(...) cerr << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)
#else
#define dbg(...) 42
#endif

inline namespace RecursiveLambda{
	template <typename Fun>
	struct y_combinator_result{
		Fun fun_;
		template <typename T> 
		explicit y_combinator_result(T &&fun): fun_(forward<T>(fun)){}
		template <typename...Args>
		decltype(auto) operator()(Args &&...args){
			return fun_(ref(*this), forward<Args>(args)...);
		}
	};
	template <typename Fun>
	decltype(auto) y_combinator(Fun &&fun){
		return y_combinator_result<decay_t<Fun>>(forward<Fun>(fun));
	}
};

void setIO(string s) // USACO
{
	#ifndef LOCAL
	    freopen((s + ".in").c_str(), "r", stdin);
	    freopen((s + ".out").c_str(), "w", stdout);
	#endif
}

/**
 * Description: modular arithmetic operations 
 * Source: 
	* KACTL
	* https://codeforces.com/blog/entry/63903
	* https://codeforces.com/contest/1261/submission/65632855 (tourist)
	* https://codeforces.com/contest/1264/submission/66344993 (ksun)
	* also see https://github.com/ecnerwala/cp-book/blob/master/src/modnum.hpp (ecnerwal)
 * Verification: 
	* https://open.kattis.com/problems/modulararithmetic
 */
template<int MOD, int RT> struct mint {
	static const int mod = MOD;
	static constexpr mint rt() { return RT; } // primitive root for FFT
	int v; explicit operator int() const { return v; } // explicit -> don't silently convert to int
	mint() { v = 0; }
	mint(ll _v) { v = int((-MOD < _v && _v < MOD) ? _v : _v % MOD);
		if (v < 0) v += MOD; }
	bool operator==(const mint& o) const{
		return v == o.v; }
	friend bool operator!=(const mint& a, const mint& b) { 
		return !(a == b); }
	friend bool operator<(const mint& a, const mint& b) { 
		return a.v < b.v; }
	friend istream& operator>>(istream& is, const mint& o){
		ll v; is >> v; o = mint(v); return is; }
	friend ostream& operator<<(ostream& os, const mint& o){
		os << o.v; return os; }
	
	mint& operator+=(const mint& m) { 
		if ((v += m.v) >= MOD) v -= MOD; 
		return *this; }
	mint& operator-=(const mint& m) { 
		if ((v -= m.v) < 0) v += MOD; 
		return *this; }
	mint& operator*=(const mint& m) { 
		v = int((ll)v*m.v%MOD); return *this; }
	mint& operator/=(const mint& m) { return (*this) *= inv(m); }
	friend mint pow(mint a, ll p) {
		mint ans = 1; assert(p >= 0);
		for (; p; p /= 2, a *= a) if (p&1) ans *= a;
		return ans; }
	friend mint inv(const mint& a) { assert(a.v != 0); 
		return pow(a,MOD-2); }
		
	mint operator-() const { return mint(-v); }
	mint& operator++() { return *this += 1; }
	mint& operator--() { return *this -= 1; }
	friend mint operator+(mint a, const mint& b) { return a += b; }
	friend mint operator-(mint a, const mint& b) { return a -= b; }
	friend mint operator*(mint a, const mint& b) { return a *= b; }
	friend mint operator/(mint a, const mint& b) { return a /= b; }
};

using Mint = mint<MOD,5>; // 5 is primitive root for both common mods


Mint dp[1 << 18];
bool comp[1 << 18];
bool g[18][18], good[18][18];
vi adj[18];



void solve()
{
	int n, m;
	cin >> n >> m;
	REP(m) {
		int u, v;
		cin >> u >> v;
		u--, v--;
		g[v][u] = 1;
		adj[u].pb(v), adj[v].pb(u);
	}
	F0R(i, n) F0R(j, n) {
		if (g[i][j] == g[j][i]) {
			good[i][j] = good[j][i] = 1;
		}
	}
	comp[0] = 1;
	F0R(mask, 1 << n) {
		F0R(i, n) {
			if (!((1 << i) & mask)) continue;
			int pmask = mask ^ (1 << i);
			if (comp[pmask] == 0) break;
			bool ok = 1;
			F0R(j, n) {
				if ((pmask & (1 << j)) && !good[i][j]) {
					ok = 0;
				}
			}
			comp[mask] = ok;
		}
	}
	dp[0] = 1;
	FOR(mask, 1, 1 << n) {
		for (int cur = mask; cur; cur = (cur - 1) & mask) {
			if (!comp[cur]) continue;
			int k = __builtin_popcount(cur);
			if (k & 1) dp[mask] += dp[mask - cur];
			else dp[mask] -= dp[mask - cur];
		}
	}
	cout << dp[(1 << n) - 1] * m / (Mint)2;
}

int32_t main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);
    int testcase=1;
    // cin >> testcase;
    while (testcase--)
    {
        solve();
    }
}

컴파일 시 표준 에러 (stderr) 메시지

amusementpark.cpp: In function 'void setIO(std::string)':
amusementpark.cpp:94:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   94 |      freopen((s + ".in").c_str(), "r", stdin);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
amusementpark.cpp:95:13: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   95 |      freopen((s + ".out").c_str(), "w", stdout);
      |      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 12 / 12
• Subtask 3: 23 / 23
• Subtask 4: 21 / 21
• Subtask 5: 37 / 37