제출 #395589

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
395589		Berted	Flood (IOI07_flood)	C++14	73 / 100	95 ms	7132 KiB

flood

#include <iostream>
#include <vector>
#include <algorithm>

#define pii pair<int, int>
#define ppi pair<pii, int>
#define fst first
#define snd second

using namespace std;

const int INF = 1e9;

int N, M; ppi A[200001]; pii C[200001];
pii adj[200001][4];

vector<int> vis;
int H[200001];

bool rem[200001], ans[200001];

int DFS(int u, int pv)
{
	int ret = H[u] + 1; 
	vis.push_back(u);

	//cerr << "D: " << u << " " << C[u].fst << " " << C[u].snd << " " << pv << "\n";
	for (int k = -1; k < 2; k++)
	{
		int nx = adj[u][(pv + 4 + k) % 4].fst, id = adj[u][(pv + 4 + k) % 4].snd;
		if (nx == -1 || rem[id]) continue;
		if (H[nx] < H[u]) {ret = min(ret, H[nx]);}
		else {H[nx] = H[u] + 1; ret = min(ret, DFS(nx, (pv + 4 + k) % 4));}
		
		rem[id] = 1;
		if (ret < H[u]) {break;}
		else if (ret == H[u]) {ret = H[u] + 1;}
		else
		{
			//cerr << "MARK: " << id << "\n";
			ans[id] = 1;
		}
	}
	//cerr << "RET: " << C[u].fst << " " << C[u].snd << " " << ret << " " << H[u] << "\n";
	return ret;
}

int main()
{
	ios :: sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> N;
	for (int i = 0; i < N; i++) 
	{
		cin >> A[i].fst.fst >> A[i].fst.snd; A[i].snd = i; H[i] = INF; 
		C[i] = A[i].fst;
		for (int j = 0; j < 4; j++) adj[i][j] = {-1, -1};
	}

	cin >> M;
	for (int i = 0; i < M; i++)
	{
		int u, v; cin >> u >> v; u--; v--;
		if (A[u].fst.fst == A[v].fst.fst)
		{
			if (A[u].fst.snd < A[v].fst.snd) {adj[u][0] = {v, i}; adj[v][2] = {u, i};}
			else {adj[u][2] = {v, i}; adj[v][0] = {u, i};}
		}
		else 
		{
			if (A[u].fst.fst < A[v].fst.fst) {adj[u][1] = {v, i}; adj[v][3] = {u, i};}
			else {adj[u][3] = {v, i}; adj[v][1] = {u, i};}
		}
	}

	sort(A, A + N);
	for (int i = 0; i < N; i++)
	{
		//cerr << "START: " << A[i].fst.fst << " " << A[i].fst.snd << " " << A[i].snd << "\n";
		H[A[i].snd] = 0; DFS(A[i].snd, 0);
		for (const int &x : vis) H[x] = INF;
		vis.clear();
	}

	vector<int> ret;
	for (int i = 0; i < M; i++)
		if (ans[i]) ret.push_back(i + 1); 

	cout << ret.size() << "\n";
	for (const int &x : ret) cout << x << "\n";
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 3 / 3
• Subtask 5: 10 / 10
• Subtask 6: 3 / 3
• Subtask 7: 3 / 3
• Subtask 8: 3 / 3
• Subtask 9: 3 / 3
• Subtask 10: 9 / 9
• Subtask 11: 9 / 9
• Subtask 12: 0 / 9
• Subtask 13: 0 / 9
• Subtask 14: 0 / 9