Submission #802939

#	Time	Username	Problem	Language	Result	Execution time	Memory
802939		tlnk07	Naboj (COCI22_naboj)	C++17	0 / 110	106 ms	9492 KiB

naboj

#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(sta.size() < n)
    {
      cout << -1;
      return 0;
    }
	cout << n << "\n";
	while(!sta.empty())
	{
		cout << sta.top() << " 1\n";
		sta.pop();
	}
}

Compilation message (stderr)

naboj.cpp: In function 'int main()':
naboj.cpp:39:18: warning: comparison of integer expressions of different signedness: 'std::stack<int>::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   39 |    if(sta.size() < n)
      |       ~~~~~~~~~~~^~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 25
• Subtask 3: 0 / 70