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#include <cstdio>
#include <algorithm>
#include <list>
#include <vector>

//#define debug(x...) fprintf(stderr, x)
#define debug(x...)  

struct CRectangle
{
	int x1, y1, x2, y2;
	CRectangle* next;
	CRectangle* prev;
};

//std::list<CRectangle> countries;
CRectangle *listRoot;
std::vector<CRectangle*> sortedList;

bool compareRectangles(CRectangle *first, CRectangle *second)
{
	if (first->x1 == second->x1)
	{
		if (first->x2 == second->x2)
		{
			if (first->y1 == second->y1)
			{
				return (first->y2 < second->y2);
			}
			else return (first->y1 < second->y1);
		}
		else return (first->x2 < second->x2);
	}
	else return (first->x1 < second->x1);
}

bool isPointInsideRectangle(const int x, const int y, const CRectangle* rect)
{
	if (x > rect->x1 && x < rect->x2 && y > rect->y1 && y < rect->y2)
	{
		return true;
	}
	return false;
}

bool rectangles_cross2(const CRectangle* first, const CRectangle* second)
{
	debug("Comparing %d %d %d %d with %d %d %d %d\n", first->x1, first->x2, first->y1, first->y2, second->x1, second->x2, second->y1, second->y2);
	if (second->x2 > first->x1 && first->x2 > second->x1 && second->y2 > first->y1 && first->y2 > second->y1)
	{
		debug("giving true\n");
		return true;
	}
	debug("giving false\n");
	return false;
}

bool rectangles_cross(const CRectangle* first, const CRectangle* second)
{
	debug("Comparing %d %d %d %d with %d %d %d %d\n", first->x1, first->x2, first->y1, first->y2, second->x1, second->x2, second->y1, second->y2);
	if (isPointInsideRectangle(first->x1, first->y1, second)
		|| isPointInsideRectangle(first->x1, first->y2, second)
		|| isPointInsideRectangle(first->x2, first->y1, second)
		|| isPointInsideRectangle(first->x2, first->y2, second)
		|| isPointInsideRectangle(second->x1, second->y1, first)
		|| isPointInsideRectangle(second->x1, second->y2, first)
		|| isPointInsideRectangle(second->x2, second->y1, first)
		|| isPointInsideRectangle(second->x2, second->y2, first)
		)
	{
		debug("giving true\n");		
		return true;
	}
	debug("giving false\n");
	return false;
}

void rectangles_merge(CRectangle& mergeTo, const CRectangle& merged)
{
	mergeTo.x1 = std::min(mergeTo.x1, merged.x1);
	mergeTo.x2 = std::max(mergeTo.x2, merged.x2);
	mergeTo.y1 = std::min(mergeTo.y1, merged.y1);
	mergeTo.y2 = std::max(mergeTo.y2, merged.y2);
}

CRectangle* checkWithAll(CRectangle* num)
{
	for (CRectangle *i = listRoot; i != NULL; i = i->next)
	{
		if (num == i) continue;
		if (rectangles_cross2(i, num))
		{
			return i;
		}
	}
	return NULL;
}

int main()
{
	int n;
	scanf("%d", &n);
	int countries = n;
	for (int i = 0; i < n; ++i)
	{
		CRectangle *tmp = new CRectangle;
		scanf("%d %d %d %d", &tmp->x1, &tmp->x2, &tmp->y1, &tmp->y2);
		if (tmp->x1 > tmp->x2) std::swap(tmp->x1, tmp->x2);
		if (tmp->y1 > tmp->y2) std::swap(tmp->y1, tmp->y2);
		
		tmp->prev = NULL;
		tmp->next = listRoot;
		listRoot = tmp;
		
		CRectangle* cur = listRoot;
		while (true)
		{
			CRectangle* found = checkWithAll(cur);
			if (NULL != found)
			{
				rectangles_merge(*found, *cur);
				countries--;
				if (cur->prev != NULL) (cur->prev)->next = cur->next;
				else listRoot = cur->next;
				if (cur->next != NULL) (cur->next)->prev = cur->prev;
				delete cur;
				cur = found;
			}			
			else break;
		}
	}
	printf("%d\n", countries);
	//sort
	for (CRectangle* i = listRoot; i != NULL; i = i->next)
	{
		sortedList.push_back(i);
	}
	std::sort(sortedList.begin(), sortedList.end(), compareRectangles);
	for (std::vector<CRectangle*>::iterator it = sortedList.begin(); it != sortedList.end(); ++it)
	{
		printf("%d %d %d %d\n", (*it)->x1, (*it)->x2, (*it)->y1, (*it)->y2);
	}
}