#include <string>
#include <map>
#include <set>
#include <fstream>
#include <vector>
#include <iostream>

using namespace std;
class Node {

	typedef set<Node*>::const_iterator node_iterator;

private:
	string name;
	set <Node*> neighboors;
	void add_neigboor(Node* neighboor);
	void remove_neighboor(Node* neighboor);

public:
	Node();
	Node(const string& aname);
	const string get_name() const;


	node_iterator nb_begin() const {
		return neighboors.begin();
	};
	node_iterator nb_end() const {
		return neighboors.end();
	};

	const bool& operator == (const Node& r);


	friend class Graph;






};


class Graph
{
	typedef set<Node*>::const_iterator node_iterator;
private:
	map <string, bool> taken_names;
	map <string, Node> saved;
	set<Node*> nodes;
	void write_graph(vector <vector <node_iterator> > ind);
public:
	Graph() {};
	void add_node(Node* node);
	void remove_node(Node* node);
	void add_edge(Node* begin, Node* end);
	void remove_edge(Node* begin, Node* end);
	//задание 
	void read_file(string file_name);
	void find_independent_graphs();


	node_iterator begin() {
		return nodes.begin();
	};

	node_iterator end() {
		return nodes.end();
	};
	friend class Node;
};

class Graph_exception {};


class BFS
{
    typedef set<Node*>::const_iterator node_iterator;
    const Graph& graph;
public:
    BFS(const Graph& agraph) : graph(agraph) {}
    bool connected(Node* begin, Node* end);
    friend Graph;
    friend Node;
};


class DFS {
    typedef set<Node*>::const_iterator node_iterator;
private:
    const Graph& graph;
    set<Node*> visited;
    bool connected(Node* begin, Node* end, int depth);
public:

    DFS(const Graph& agraph) : graph(agraph) {}
    bool connected(Node* begin, Node* end);
    friend Graph;
    friend Node;
};