#include <bits/stdc++.h>
using namespace std;
vector<int> edges[100001];
vector<int> v;
vector<int> visited(100001,0);
void dfs(int i, int prev)
{
visited[i]=1;
for(int j:edges[i])
{
if(visited[j]==0)
{
v.push_back(j);
dfs(j,i);
}
else if(j!=prev && prev!=0)
{
vector<int> ans;
int index;
for(int k=0;k<(int)v.size();k++)
{
if(v[k]==j)
{
index=k;
break;
}
}
for(int k=index;k<(int)v.size();k++)
ans.push_back(v[k]);
ans.push_back(j);
cout<<ans.size()<<"\n";
for(auto &i1:ans)
cout<<i1<<" ";
exit(0);
}
}
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n, m;
cin >> n >> m;
for (int i = 0; i < m; i++)
{
int a, b;
cin >> a >> b;
edges[a].push_back(b);
edges[b].push_back(a);
}
for(int i=1;i<=n;i++)
{
if(visited[i]==0)
{
v.push_back(i);
dfs(i, 0);
v.clear();
}
}
cout<<"IMPOSSIBLE";
return 0;
}
Try this case...
4 4
1 2
1 3
3 4
1 4
Hope now you can debug your code yourself :)
thanks
It passed all testcase !!