function doDfs(G[n]: Graph): 
   visited = array[n, false]
          
   function DFS(u: int):   
      visited[u] = true
      for v: (u, v) in G:      
         if not visited[v]:               
            DFS(v)

   for i = 1 to n:             
      if not visited[i]:                   
         DFS(i)