3 solutions

  • 0
    @ 2026-2-25 20:02:28
    #include<bits/stdc++.h>
    using namespace std;
    const int N=2e5+10;
    vector<int> g[N]; //g[i]里面储存的是i可以走到的所有点 
    void dfs(int u,int fa)
    {
    	cout<<u<<" ";
    	for(auto j:g[u])
    	{
    		if(j==fa) continue;
    		dfs(j,u);
    		cout<<u<<" ";
    	}
    }
    int main()
    {
    	int n;
    	cin>>n;
    	for(int i=1;i<n;i++)
    	{
    		int a,b;
    		cin>>a>>b;
    		g[a].push_back(b);
    		g[b].push_back(a); 
    	}
    	for(int i=1;i<=n;i++)
    	{
    		sort(g[i].begin(),g[i].end());
    	}
    	dfs(1,-1);//当前点和当前点的父节点 
    	return 0;
    }
    
    

    Information

    ID
    2772
    Time
    1000ms
    Memory
    256MiB
    Difficulty
    3
    Tags
    # Submissions
    14
    Accepted
    9
    Uploaded By