Given N nodes and E edges of a graph. The task is to do depth first traversal of the graph.

Note: Use recursive approach.

Input:
First line of input contains number of testcases T. For each testcase. First line of each testcase contains number of nodes and edges seperated by space and next line contains N pairs of integers (X and Y each) where X Y means an edge from X to Y.

Output:
For each testcase, print the nodes while doing DFS starting from node 0.

Your task:
The task is to complete the function dfs() which should do the depth first traversal of given graph and prints the node in DFS order.

Constraints:
1 <= T <= 100
1 <= N <= 500

Example:
Input:
2
5 4
0 1 0 2 0 3 2 4
4 3
0 1 1 2 0 3

Output:
0 1 2 4 3    // dfs from node 0
0 1 2 3

Explanation:
Testcase 1: There is  one test cases.  First line of each test case represent an integer N denoting number of edges and then in the next line N pairs of values a and b are fed which denotes there is an edge from a to b.
 

** For More Input/Output Examples Use 'Expected Output' option **