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

using namespace std;

const int MAX = 100 * 1000;
const int INF = (int)10e9;

int N;

struct Pair
{
	int *first;
	int second;
	Pair():first(NULL), second(0){}
	Pair(int *first, int second):first(first), second(second){}
};

vector<Pair> Sorted;

struct Rect
{	
	int left, right, top, bot;
	int l;
	int r;
	Rect():left(0), right(0), top(0), bot(0), l(NULL), r(NULL){}
	Rect(int left, int right, int top, int bot)
	:left(left), right(right), top(top), bot(bot), l(NULL), r(NULL) {}
	void load(int id)
	{
		scanf("%d %d %d %d", &left, &right, &bot, &top);
		l = left;
		r = -right;
		Sorted[id*2] = Pair(&l,id);
		Sorted[id*2+1] = Pair(&r,id);
		
	}

	static Rect boundary(Rect a, Rect b)
	{
		return Rect(min(a.left, b.left), max(a.right, b.right), max(a.top, b.top), min(a.bot, b.bot));
	}

	static bool less(Rect a, Rect b)
	{
		if(a.left < b.left) return true;
		else if(a.left > b.left) return false;
		else if(a.right < b.right) return true;
		else if(a.right > b.right) return false;
		else if(a.bot < b.bot) return true;
		else if(a.bot > b.bot) return false;
		else if(a.top < b.top) return true;
		else if(a.top > b.top) return false;
	}

};

bool comp(Pair a, Pair b)
{
	if((*a.first)+(*b.first) == 0 && (*a.first)<0) return true;
	int aa = (*a.first)<0?-(*a.first):(*a.first);
	int bb = (*b.first)<0?-(*b.first):(*b.first);
	return aa<bb?true:false;
}

vector<Rect> TAB;
int Used[MAX];

void DeleteAndInsert(int a, int b, Rect c)
{
	if(b<a) swap(a,b);

	(TAB[a].l) = c.left;
	(TAB[a].r) = -c.right;
	(TAB[b].l) = INF;
	(TAB[b].r) = INF;
	c.l = TAB[a].l;
	c.r = TAB[a].r;

	swap(TAB[b], TAB[N-1]);
	TAB.pop_back();
	TAB[a] = c;
	N--;

	sort(Sorted.begin(), Sorted.end(), comp);
	Sorted.pop_back();
	Sorted.pop_back();
};

void Insert()
{
	bool change = true;

	vector<int> in;
	vector<Pair> que;

	sort(Sorted.begin(), Sorted.end(), comp);

	while(change)
	{
		change = false;
		try{
			int inside = 0;
			for(int i = 0; i<2*N; i++)
			{
				if(*Sorted[i].first >= 0)
				{
					in.push_back(Sorted[i].second);
					Used[Sorted[i].second] = inside;
					inside++;
				}
				else
				{
					if(inside == 1)
					{
						inside--;
						in.pop_back();
					}
					else if(inside > 1)
					{
						for(int j = 0; j<inside; j++)
						{
							que.push_back(Pair(new int(-TAB[in[j]].bot), in[j]));
							que.push_back(Pair(&(TAB[in[j]].top), in[j]));
						}
						sort(que.begin(), que.end(), comp);
						int res = 0;
						int id;
						for(int j = que.size()-1; j>=0; j--)
						{
							int cur = *que[j].first;
							if(cur>=0)
							{
								res++;
								if(res == 2)
								{
									//w id oraz w que[j].second mamy przeciecie
									Rect c = Rect::boundary(TAB[id], TAB[que[j].second]);
									DeleteAndInsert(id, que[j].second, c);
									throw 0;
								}
								else id = que[j].second;
							}
							else
							{
								res--;
							}
							que.pop_back();
						}
						inside--;
						Used[in[inside]] = Used[Sorted[i].second];
						swap(in[Used[Sorted[i].second]], in[inside]);
						in.pop_back();
					}
				}
			}

		}catch(int code)
		{
			in = vector<int>(0);
			que = vector<Pair>(0);
			change = true;
		}
	}

}

int main()
{
	scanf("%d", &N);
	TAB.resize(N);
	Sorted.resize(2*N);
	for(int i = 0; i<N; i++) TAB[i].load(i);

	Insert();
	
	sort(TAB.begin(), TAB.end(), Rect::less);

	printf("%d\n", N);
	for(int i = 0; i<N; i++)
	{
		printf("%d %d %d %d\n", TAB[i].left, TAB[i].right, TAB[i].bot, TAB[i].top);
	}

	return 0;
}