Bai4_Topo_sort

class Graph {

    int V;
    Adjacency* adj;

public:
    Graph(int V){
        this->V = V;
        adj = new Adjacency[V];
    }
    void addEdge(int v, int w){
        adj[v].push(w);
    }

    //Heling functions
   void  topologicalSortUtil(int v, bool visited[],
                                list<int>& Stack)
{
    // Mark the current node as visited.
    visited[v] = true;

    // Recur for all the vertices
    // adjacent to this vertex
    int size = adj[v].getSize();
    for (int i = 0;  i  < size; ++i)
        {
            int ele = adj[v].getElement(i);
            if (!visited[ele])
            topologicalSortUtil(ele, visited, Stack);
        }

    // Push current vertex to stack
    // which stores result
    Stack.push_front(v);
}
    void topologicalSort(){
       list<int> Stack;

    // Mark all the vertices as not visited
    bool* visited = new bool[V];
    for (int i = 0; i < V; i++)
        visited[i] = false;

    // Call the recursive helper function
    // to store Topological
    // Sort starting from all
    // vertices one by one
    for (int i = 0; i < V; i++)
        if (visited[i] == false)
            topologicalSortUtil(i, visited, Stack);

    // Print contents of stack
    while (Stack.empty() == false) {
        cout << Stack.front() << " ";
        Stack.pop_front();
    }
    }
};