제출 #427159

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
427159		pavement	Port Facility (JOI17_port_facility)	C++17	22 / 100	6127 ms	652724 KiB

port_facility

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
//#define int long long
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define ppb pop_back
#define eb emplace_back
#define g0(a) get<0>(a)
#define g1(a) get<1>(a)
#define g2(a) get<2>(a)
#define g3(a) get<3>(a)
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef double db;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> ii;
typedef tuple<int, int, int> iii;
typedef tuple<int, int, int, int> iiii;
typedef tree<ii, null_type, less<ii>, rb_tree_tag, tree_order_statistics_node_update> ordered_set;

int N, ans, L[1000005], R[1000005], link[1000005], sz[1000005], r[1000005];
bool inv, vis[1000005], col[1000005], cl[1000005];
vector<int> curr, adj[1000005];
const int MOD = 1e9 + 7;

bool is(int a, int b) {
	if (L[a] > L[b]) return is(b, a);
	return R[b] > R[a] && R[a] > L[b];
}

int find(int x) {
	if (x == link[x]) return x;
	return link[x] = find(link[x]);
}

void unite(int a, int b) {
	a = find(a);
	b = find(b);
	if (a == b) return;
	if (sz[b] > sz[a]) swap(a, b);
	sz[a] += sz[b];
	link[b] = a;
}

void dfs(int n) {
	vis[n] = 1;
	for (auto u : adj[n])
		if (vis[u]) {
			if (col[u] == col[n]) inv = 1;
		} else {
			col[u] = col[n] ^ 1;
			dfs(u);
		}
}

main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> N;
	for (int i = 1; i <= N; i++) {
		link[i] = i;
		sz[i] = 1;
		cin >> L[i] >> R[i];
		cl[R[i]] = 1;
		r[L[i]] = r[R[i]] = i;
	}
	for (int i = 1; i <= 2 * N; i++) {
		if (cl[i]) {
			int pos = -1;
			for (int j = (int)curr.size() - 1; j >= 0; j--) {
				if (r[i] == curr[j]) {
					pos = j;
					break;
				} else adj[r[i]].pb(curr[j]), adj[curr[j]].pb(r[i]), unite(r[i], curr[j]);
			}
			assert(pos != -1);
			curr.erase(curr.begin() + pos);
		} else {
			curr.pb(r[i]);
		}
	}
	for (int i = 1; i <= N; i++)
		if (!vis[i]) dfs(i);
	if (inv) cout << "0\n";
	else {
		ans = 1;
		for (int i = 1; i <= N; i++)
			if (i == find(i)) ans *= 2, ans %= MOD;
		cout << ans << '\n';
	}
}

컴파일 시 표준 에러 (stderr) 메시지

port_facility.cpp:63:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   63 | main() {
      | ^~~~

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 56
• Subtask 4: 0 / 22