def SCCSearch_DFS(self, v, explored_list, leaders):
    explored_list[v] = True
    for u in self.graph[v]:
        if (not explored_list[u]):
            leaders.append(u)
            self.SCCSearch_DFS(u, explored_list, leaders)
    self.t += 1
    self.finish_time[v] = self.t
def SCCSearch_DFS(self, v, explored_list, leaders):
    explored_list[v] = True
    for u in self.graph[v]:
        if (not explored_list[u]):
            leaders.append(u)
            self.SCCSearch_DFS(u, explored_list, leaders)
    self.t += 1
    self.finish_time[v] = self.t