1 import java.util.Scanner;
2
3 public class Main {
4
5 public static int[] visit = new int[1000];
6 public static int[][] map = new int[1000][1000];
7
8 public static void main(String[] args) {
9 Scanner input = new Scanner(System.in);
10 int T = input.nextInt();
11 for (int x = 0; x < T; x++) {
12 int n = input.nextInt(), m = input.nextInt();
13 for (int i = 0; i <n; i++) {
14 for(int j=0;j<n;j++)
15 map[i][j] = 0;
16 visit[i] = 0;
17 }
18 for (int i = 0; i < m; i++) {
19 int a = input.nextInt();
20 int b = input.nextInt();
21 map[a][b] = map[b][a] = 1;
22 }
23 System.out.print(0);
24 DFS(0, n);
25 System.out.println();
26 }
27 }
28
29 public static void DFS(int temp, int m) {
30 visit[temp] = 1;
31 for (int i = 0; i <m; i++) {
32 if (visit[i] == 0 && map[temp][i] == 1) {
33 System.out.print(" " + i);
34 DFS(i, m);
35 }
36 }
37 }
38 }
