Medium

26%

Given a directed graph you need to complete the function **topoSort** which returns an array having the topologically sorted elements of the array and takes two arguments . The first argument is the Graph **graph **represented as adjacency list and the second is the number of vertices **N** .

**Note : **There can be multiple topological sorts of a Graph. The driver program that calls your function doesn't match your output element by element, but checks whether the output produced by your function is a valid topological sort or not.

**Input:**

The first line of input takes the no of test cases then T test cases follow . Each test case contains two lines . The first line of each test case contains two integers E and N representing no of edges and the no of vertices . Then in the next line are E pairs of integers u v representing an edge from u to v in the graph.

**Output:**

For each test case output will be 1 if the topological sort is done correctly else it will be 0 .

**Constraints:**

1<=T<=50

1<=E,N<=50

0<=u,v

**Example:**

**Input**

1

6 6

5 0 5 2 2 3 4 0 4 1 1 3

**Output**

1

The output 1 denotes that the order is valid. So if you have implemented your function correctly, then output would be 1 for all test cases.

**Note:**The **Input/Ouput** format and **Example** given are used for system's internal purpose, and should be used by a user for **Expected Output** only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.