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#include <iostream>
#include <map>
#include <list>
#include <sstream>
#include <conio.h>

struct Coord
{
	Coord() {memset(this, NULL, sizeof(this));}
	Coord(int _x, int _y) : x(_x), y(_y) {}
	int x, y;

	friend bool operator<(const Coord& a, const Coord& b) 
	{ if (a.y==b.y) return a.x<b.x; else return a.y<b.y; } // for std::map

	friend bool operator==(const Coord& a, const Coord& b) 
	{ return a.x==b.x && a.y==b.y; }

	friend Coord operator+(const Coord& a, const Coord& b) 
	{ return Coord(a.x+b.x, a.y+b.y); }

	friend std::ostream& operator<<(std::ostream& o, const Coord& a)
	{ std::stringstream s; s << "[" << a.x << "," << a.y << "]"; o << s.str(); return o; }
};

struct LongestDistance
{
	LongestDistance() {memset(this, NULL, sizeof(this));}
	Coord a, b;
	int distance;
};

struct Node
{
	Node(bool _open=true, bool _visited=false, int _distance=0) : 
	open(_open), visited(_visited), distance(_distance) {}

	bool open;
	bool visited;
	int distance;
};

class Graph
{
public:
	Graph(int sx, int sy)
	{
		for (int i = 0; i<sx; ++i)
		{
			for (int j = 0; j<sy; ++j)
				m_map[Coord(i,j)] = Node();
		}
		m_best.distance = 0;

		// the four basic directions
		dirs.push_back(Coord(0, -1));
		dirs.push_back(Coord(1, 0));
		dirs.push_back(Coord(0, 1));
		dirs.push_back(Coord(-1, 0));
	}
	~Graph() {}

	void set_open(const Coord& c, bool flag)
	{
		if (m_map.find(c)!=m_map.end())
			m_map[c].open = flag;
	}

	void reset()
	{
		for(Map::iterator it = m_map.begin(); it != m_map.end(); ++it)
		{
		    (*it).second.distance = INT_MAX;
			(*it).second.visited = false;
		}
	}

	void dijkstra(const Coord& start)
	{
		reset();

		Map::iterator current = m_map.find(start);
		(*current).second.distance = 0;

		std::list<Map::iterator> queue;
		queue.push_back(current);

		while (queue.size()!=0)
		{
			// find next node to compute
			current = *queue.begin();
			for(std::list<Map::iterator>::iterator it = queue.begin(); it != queue.end(); ++it)
			{
			    if ((**it).second.distance<(*current).second.distance)
					current = (*it);
			}
			queue.remove(current);

			// consider neighbours
			for (std::list<Coord>::const_iterator it = dirs.begin(); it != dirs.end(); ++it) // step in every direction
			{
			    Map::iterator ni = m_map.find((*current).first+(*it));
				if (ni!=m_map.end() && !(*ni).second.visited)
				{
					Node* n = &(*ni).second;
					if (n->open)// && !n->visited)
					{
						int dist = (*current).second.distance+1;
						if (dist<n->distance)
							n->distance = dist;
						queue.push_back(ni);
					}
				}
			}
			//print_ascii();
			//_getch();
			(*current).second.visited = true;
		}

		// update m_best
		Map::iterator longest = m_map.end();
		for (Map::iterator it = m_map.begin(); it != m_map.end(); ++it)
		{
			if ((*it).second.open && (*it).second.distance!=INT_MAX)
				if (longest==m_map.end() || (*it).second.distance>(*longest).second.distance)
					longest = it;
		}
		if ((*longest).second.distance>m_best.distance)
		{
			m_best.a = start;
			m_best.b = (*longest).first;
			m_best.distance = (*longest).second.distance;
		}
	}

	void dijkstra_all()
	{
		m_best.distance = 0;
		for(Map::const_iterator it = m_map.begin(); it != m_map.end(); ++it)
		{
		    if ((*it).second.open)
				dijkstra((*it).first);
			//print_ascii();
			//_getch();
		}
	}

	void print_ascii()
	{
		// marks the two best points with an X
		for(Map::const_iterator it = m_map.begin(); it != m_map.end(); ++it)
		{
			std::cout << ((*it).first.x==0?"\n":"");
			if ((*it).first==m_best.a || (*it).first==m_best.b)
			{
				std::cout << "X";
				//std::cout << (*it).second.distance;
			}
			else
			{
				//if ((*it).second.visited)
				//	std::cout << (*it).second.distance; // looks good until distance becomes two digit
				//else
					std::cout << ((*it).second.open?".":"#");
			}
		}
		std::cout << std::endl;
	}

	const LongestDistance&	best()	{ return m_best; }

private:
	typedef std::map<Coord, Node>	Map;
	Map								m_map;
	LongestDistance					m_best;
	std::list<Coord>				dirs;
};

int main()
{
	int sizex = 15;
	int sizey = 15;

	Graph g(sizex, sizey);

	// make a open area enclosed with blocked squares
	// longest route should be a diagonal
	for (int y = 0; y<=sizey; ++y)
	{
		for (int x = 0; x<=sizex; ++x)
			g.set_open(Coord(x,y), !(x==0 || y==0 || x==sizex-1 || y==sizey-1));
	}

	// run for one
	//g.dijkstra(Coord(1,1));
	g.dijkstra_all();
	g.print_ascii();

	std::cout << g.best().a << " " << g.best().b << " " << g.best().distance << std::endl;
	return 1;
}