Submission #598937

# Submission time Handle Problem Language Result Execution time Memory
598937 2022-07-19T08:09:06 Z 장태환(#8458) Potemkin cycle (CEOI15_indcyc) C++17
60 / 100
38 ms 4220 KB
#include <bits/stdc++.h>
#include <assert.h>
using namespace std;
int num[1010];
int depth[1010];
vector<pair<int, int>> maxbe[1010];
int cnt[1010];
int par[1010];
vector<int>link[1010];
bool arr[1010][1010];
vector<pair<int, int>>t;
int c;
bitset<1024>cn[1010];
void dfs(int n, int p = 0, int d = 0)
{
	depth[n] = d;
	num[n] = ++c;
	par[n] = p;
	int i;
	for (i = 0; i < link[n].size(); i++)
	{
		if (link[n][i] == p)
			continue;
		if (num[link[n][i]])
		{
			if (depth[link[n][i]] < d)
			{
				if (arr[n][link[n][i]])
					continue;
				arr[n][link[n][i]] = 1;
				maxbe[n].push_back({ depth[link[n][i]],link[n][i] });
				t.push_back({ n,link[n][i] });
			}
			else
			{
				if (arr[link[n][i]][n])
					continue;
				arr[link[n][i]][n] = 1;
				maxbe[link[n][i]].push_back({ d,n });
				t.push_back({ link[n][i],n });
			}
		}
		else
		{
			dfs(link[n][i], n, d + 1);
		}
	}
}
int main()
{
	srand(time(NULL));
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	int N, M;
	cin >> N >> M;
	int i;
	for (i = 0; i < M; i++)
	{
		int a, b;
		cin >> a >> b;
		link[a].push_back(b);
		link[b].push_back(a);
		cn[a].set(b);
		cn[b].set(a);
	}
	int T = 1;
	while (T--)
	{
		memset(arr, 0, sizeof(arr));
		memset(num, 0, sizeof(num));
		memset(depth, 0, sizeof(depth));
		t.clear();
		memset(par, 0, sizeof(par));
		c = 0;
		for (i = 1; i <= N; i++)
		{
			maxbe[i].clear();
			sort(link[i].begin(), link[i].end());
		}
		vector<int>od;
		for (i = 1; i <= N; i++)
		{
			od.push_back(N-i-1);
		}

		for (i = 1; i <= N; i++)
		{
			if (!num[od[i - 1]])
			{
				dfs(od[i - 1]);
			}
		}
		for (i = 1; i <= N; i++)
		{
			sort(maxbe[i].begin(), maxbe[i].end());
		}
		for (i = 0; i < t.size(); i++)
		{
			vector<int>ans;
			int c = -1;
			while (depth[t[i].first] > depth[t[i].second])
			{
				c++;
				ans.push_back(t[i].first);
				pair<int, int>xe;
				xe.first = depth[t[i].second] + (c == 0);
				xe.second = 0;
				auto ne = lower_bound(maxbe[t[i].first].begin(), maxbe[t[i].first].end(), xe) - maxbe[t[i].first].begin();
				if (ne != maxbe[t[i].first].size())
				{
					t[i].first = maxbe[t[i].first][ne].second;
				}
				else
					t[i].first = par[t[i].first];
			}
			ans.push_back(t[i].second);
			if (ans.size() <= 3)
			{
				continue;
			}
			for (i = 0; i < ans.size(); i++)
				cout << ans[i] << ' ';
			return 0;
		T:
			int d;
		}

	}
	cout << "no";
}

Compilation message

indcyc.cpp: In function 'void dfs(int, int, int)':
indcyc.cpp:20:16: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |  for (i = 0; i < link[n].size(); i++)
      |              ~~^~~~~~~~~~~~~~~~
indcyc.cpp: In function 'int main()':
indcyc.cpp:97:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   97 |   for (i = 0; i < t.size(); i++)
      |               ~~^~~~~~~~~~
indcyc.cpp:109:12: warning: comparison of integer expressions of different signedness: 'long int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |     if (ne != maxbe[t[i].first].size())
      |         ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
indcyc.cpp:121:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  121 |    for (i = 0; i < ans.size(); i++)
      |                ~~^~~~~~~~~~~~
indcyc.cpp:125:8: warning: unused variable 'd' [-Wunused-variable]
  125 |    int d;
      |        ^
indcyc.cpp:124:3: warning: label 'T' defined but not used [-Wunused-label]
  124 |   T:
      |   ^
# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
2 Correct 1 ms 1364 KB Output is correct
3 Correct 1 ms 1364 KB Output is correct
4 Correct 1 ms 1364 KB Output is correct
5 Correct 1 ms 1364 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
2 Correct 1 ms 1364 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 1364 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 1364 KB Expected integer, but "no" found
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 2 ms 1492 KB Output is correct
2 Correct 2 ms 1492 KB Output is correct
3 Correct 3 ms 1620 KB Output is correct
4 Correct 3 ms 1620 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 2 ms 1492 KB Expected integer, but "no" found
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 15 ms 2956 KB Output is correct
2 Correct 7 ms 2260 KB Output is correct
3 Correct 19 ms 3024 KB Output is correct
4 Correct 9 ms 2260 KB Output is correct
# Verdict Execution time Memory Grader output
1 Incorrect 8 ms 2260 KB Expected integer, but "no" found
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Incorrect 38 ms 4220 KB Expected integer, but "no" found
2 Halted 0 ms 0 KB -