제출 #115907

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
115907		tutis	Potemkin cycle (CEOI15_indcyc)	C++17	50 / 100	1078 ms	1384 KiB

indcyc

/*input
5 6
1 2
1 3
2 3
4 3
5 2
4 5

*/
#pragma GCC optimize ("O3")
#include <bits/stdc++.h>
using namespace std;
vector<int>adj[1010];
vector<int>x;
bool yra[1010];
int pos[1010];
void ieskom(int i, int p)
{
	if (yra[i])
		return;
	pos[i] = x.size();
	x.push_back(i);
	yra[i] = true;
	int maxi = -1;
	for (int j : adj[i])
	{
		if (yra[j] && j != p)
		{
			maxi = max(maxi, pos[j]);
		}
	}
	if (maxi == -1)
		for (int j : adj[i])
		{
			ieskom(j, i);
		}
	else
	{
		vector<int>ciklas;
		for (int t = maxi; t < (int)x.size(); t++)
		{
			ciklas.push_back(x[t]);
		}
		if (ciklas.size() >= 4)
		{
			for (int i : ciklas)
				cout << i << " ";
			exit(0);
		}
	}
	yra[i] = false;
	x.pop_back();
}
int pa[1010];
int root(int x)
{
	if (pa[x] == x)
		return x;
	return pa[x] = root(pa[x]);
}
int main()
{
	ios_base::sync_with_stdio(false);
	int n, r;
	cin >> n >> r;
	for (int i = 1; i <= n; i++)
		pa[i] = i;
	while (r--)
	{
		int a, b;
		cin >> a >> b;
		adj[a].push_back(b);
		adj[b].push_back(a);
		pa[root(a)] = root(b);
	}
	vector<int>k[n + 1];
	for (int i = 1; i <= n; i++)
		k[root(i)].push_back(i);
	for (int i = 1; i <= n; i++)
	{
		if (k[i].empty())
			continue;
		for (int t = 0; t < 20; t++)
		{
			int j = k[i][rand() % k[i].size()];
			ieskom(j, -3);
		}
	}
	cout << "no\n";
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10