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  1. import java.util.*;
  2. import java.io.*;
  3.  
  4. class Main 
  5. {
  6.  
  7. 	public static void dfs(int src, List<List<Integer>> adj, int visited[], int parent[] )
  8. 	{
  9. 		visited[src]=1;
  10. 		// parent[src]=0;
  11.  
  12. 			System.out.print(src+" ");
  13. 		for(int neighbour: adj.get(src))
  14. 		{
  15. 			if(visited[neighbour]==0)
  16. 			{
  17. 				parent[neighbour]=src;
  18. 				dfs(neighbour, adj,visited,parent);
  19. 			}
  20. 		}
  21.  
  22. 	}
  23.     public static void main(String[] args) 
  24.     {
  25.         Scanner sc = new Scanner(System.in);
  26.         int t = sc.nextInt();
  27.  
  28.         while (t-- > 0) {
  29.             int n = sc.nextInt();
  30.             int e = sc.nextInt();
  31.  
  32.             List<List<Integer>> adj=new ArrayList<>();
  33.             for(int i=0;i<=n;i++)
  34.             adj.add(new ArrayList<>());
  35.  
  36.  
  37.             for (int k = 0; k < e; k++) {
  38.                 int u = sc.nextInt();
  39.                 int v = sc.nextInt();
  40.                 adj.get(u).add(v);
  41.                 adj.get(v).add(u);
  42.             }
  43.  
  44.             int visited[]=new int[n+1];
  45.             int level[]=new int[n+1];
  46.             int ways[]=new int[n+1];
  47.             int parent[]=new int[n+1];
  48.             // parent[source]=0;
  49.  
  50.               int source =sc.nextInt();
  51.               dfs(source,adj,visited,parent);
  52.  
  53.               	System.out.println();
  54.  
  55.               for(int i=1;i<=n;i++)
  56.               System.out.println(i+" "+parent[i]);
  57.  
  58.  
  59.     }
  60. }
  61. }
Success #stdin #stdout 0.24s 60840KB
comments (?)
stdin 
1
5 5
1 2
1 3
2 4
3 4
4 5
1
stdout 
1 2 4 3 5 
1 0
2 1
3 4
4 2
5 4
https://ideone.com/NS9Lf7
language:
Java (HotSpot 12)
created:
4 days ago
visibility:
public

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