oj.uz

Submission #802053

# Submission time Handle Problem Language Result Execution time Memory
802053 2023-08-02T09:25:36 Z tlnk07 Naboj (COCI22_naboj) C++17
0 / 110
 95 ms 9280 KB 
#include<bits/stdc++.h>
using namespace std;

long long n, m, x, y;
vector<int> vec[200001]; 
stack<int> sta;
bool check = 0, visited[200001];

void dfs(int x)
{
	if(visited[x])	check = true;
	if(check)	return;
	visited[x] = true;
	for(int c : vec[x])
	{
		if(!visited[c])	dfs(c);
		else	check = true;
		if(check)	return;
	}
	sta.push(x);
}

int main()
{
	memset(visited, 0, sizeof(visited));
	cin >> n >> m;
	for(int i = 1; i <= m; ++i)
	{
		cin >> x >> y;
		vec[y].push_back(x);
	}
	for(int i = 1; i <= n; ++i)
	{
		if(!visited[i])	
		{
			dfs(i);
			if(check)
			{
				cout << -1;
				return 0;
			}
		}
	}
	cout << sta.size() << "\n";
	while(!sta.empty())
	{
		cout << sta.top() << " 1\n";
		sta.pop();
	}
}

Subtask #1
0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 5076 KB Output is correct
2 Correct 2 ms 5076 KB Output is correct
3 Correct 2 ms 5076 KB Output is correct
4 Correct 3 ms 5076 KB Output is correct
5 Correct 2 ms 5076 KB Output is correct
6 Correct 2 ms 5076 KB Output is correct
7 Correct 2 ms 5076 KB Output is correct
8 Incorrect 2 ms 5076 KB Output isn't correct
9 Halted 0 ms 0 KB -

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Incorrect 95 ms 9280 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 5076 KB Output is correct
2 Correct 2 ms 5076 KB Output is correct
3 Correct 2 ms 5076 KB Output is correct
4 Correct 3 ms 5076 KB Output is correct
5 Correct 2 ms 5076 KB Output is correct
6 Correct 2 ms 5076 KB Output is correct
7 Correct 2 ms 5076 KB Output is correct
8 Incorrect 2 ms 5076 KB Output isn't correct
9 Halted 0 ms 0 KB -