C++ Program to Check Whether it is Weakly Connected or Strongly Connected for a Directed Graph

Weakly or Strongly Connected for a given a directed graph can be find out using DFS. This is a C++ program of this problem.

Functions used

Begin
   Function fillorder() = fill stack with all the vertices.
   a) Mark the current node as visited and print it
   b) Recur for all the vertices adjacent to this vertex
   c) All vertices reachable from v are processed by now, push v to Stack
End
Begin
   Function DFS() :
   a) Mark the current node as visited and print it
   b) Recur for all the vertices adjacent to this vertex
End

Example

#include 
#include 
#include 
using namespace std;
class G {
   int m;
   list *adj;
   //declaration of functions
   void fillOrder(int n, bool visited[], stack &Stack);
   void DFS(int n, bool visited[]);
   public:
      G(int N); //constructor
      void addEd(int v, int w);
      int print();
      G getTranspose();
};
G::G(int m) {
   this->m = m;
   adj = new list [m];
}
void G::DFS(int n, bool visited[]) {
   visited[n] = true; // Mark the current node as visited and print it
   cout ::iterator i;
   //Recur for all the vertices adjacent to this vertex
   for (i = adj[n].begin(); i != adj[n].end(); ++i)
      if (!visited[*i])
         DFS(*i, visited);
}
G G::getTranspose() {
   G g(m);
   for (int n = 0; n::iterator i;
      for (i = adj[n].begin(); i != adj[n].end(); ++i) {
         g.adj[*i].push_back(n);
      }
   }
   return g;
}
void G::addEd(int v, int w) {
   adj[v].push_back(w); //add w to v's list
}
void G::fillOrder(int v, bool visited[], stack &Stack) {
   visited[v] = true; //Mark the current node as visited and print it
   list::iterator i;
   //Recur for all the vertices adjacent to this vertex
   for (i = adj[v].begin(); i != adj[v].end(); ++i)
      if (!visited[*i])
         fillOrder(*i, visited, Stack);
         Stack.push(v);
}
int G::print() //print the solution {
   stack Stack;
   bool *visited = new bool[m];
   for (int i = 0; i  1) {
      cout 
Output
Following are strongly connected components in given graph
4
0 1 2 3
Graph is weakly connected.