Solution: Check if a Graph is Strongly Connected

#include "Graph.h"
void Graph::utilityFunction(int v, vector <bool>& visited) {
  visited[v] = true;
  list <int> ::iterator i;
  for (i = adjacencyList[v].begin(); i != adjacencyList[v].end(); ++i)
    if (visited[ * i] == false)
      utilityFunction( * i, visited);
}
bool Graph::isStronglyConnected() {
  vector <bool> visited(this -> vertices);
  for (int i = 0; i < this -> vertices; i++)
    visited[i] = false;
  // check graph for unvisited vertices
  utilityFunction(0, visited);
  
  // if graph has any unvisited nodes return false
  for (int i = 0; i < this -> vertices; i++)
    if (visited[i] == false)
      return false;
  // NOW CHECK FOR TRANSPOSED GRAPH 
  
  // find the transpose of the graph
  Graph gTranspose = getTranspose();
  for (int i = 0; i < this -> vertices; i++)
    visited[i] = false;
 
  // check transposed graph for non visited vertices
  gTranspose.utilityFunction(0, visited);
  
  // if transpose of graph has any unvisited nodes return false
  for (int i = 0; i < this -> vertices; i++)
    if (visited[i] == false)
      return false;
  return true;
}
int main() {
  Graph g1(5);
  g1.addEdge(0, 1);
  g1.addEdge(1, 2);
  g1.addEdge(2, 3);
  g1.addEdge(3, 0);
  g1.addEdge(2, 4);
  g1.addEdge(4, 2);
  
  if(g1.isStronglyConnected())
    cout << "Yes Graph1 is strongly connected\n"; 
  else
    cout << "No Graph1 is not strongly connected\n";
  Graph g2(4);
  g2.addEdge(0, 1);
  g2.addEdge(1, 2);
  g2.addEdge(2, 3);
  
  if(g2.isStronglyConnected())
    cout << "Yes Graph2 is strongly connected\n"; 
  else
    cout << "No Graph2 is not strongly connected\n";
  return 0;
}