Topological sort

PROBLEM :
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 V .

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 V 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,V<=50
0<=u,v<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.

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SIMPLE c++ IMPLEMENTATION :
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/* You need to complete this function */

void Topological(int ,bool [],stack<int> &,vector<int> [] ) ;
int * topoSort(vector<int> graph[], int V)
{
    bool visited[V] ;
    stack<int> stak ;
   
    for(int i=0;i<V;i++)
        visited[i]=false ;
       
    for(int i=0;i<V;i++)
    {
        if(visited[i]!=true)
            Topological(i,visited,stak,graph) ;
    }
   
    int *arr=new int[V]; ;
    int i=0 ;
    while(!stak.empty())
    {
        arr[i++]=stak.top() ;
        stak.pop() ;
    }
   
    return arr ;
}

void Topological(int data,bool visited[],stack<int> &stak,vector<int> graph[])
{
    visited[data]=true ;
   
    vector<int>::iterator i ;
    for(i=graph[data].begin();i!=graph[data].end();i++)
    {
        if(visited[*i]!=true)
            Topological(*i,visited,stak,graph) ;
    }
    stak.push(data) ;
}

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