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#include <set>
#include <vector>
#include <cstdio>
using namespace std;
int n, last;
const int MAXN = 100005;

struct rectangle
{
	int xl,xr;
	int yb,yt;
}rec[MAXN*2];


struct byBegin
{
	bool operator()(const int &a, const int &b)
	{
		if(rec[a].xl != rec[b].xl)
			return rec[a].xl < rec[b].xl;
		if(rec[a].xr != rec[b].xr)
			return rec[a].xr < rec[b].xr;
		if(rec[a].yb != rec[b].yb)
			return rec[a].yb < rec[b].yb;
		if(rec[a].yt != rec[b].yt)
			return rec[a].yt < rec[b].yt;
		return a < b;
	}
};

struct byEnd
{
	bool operator()(const int &a, const int &b)
	{
		if(rec[a].xr != rec[b].xr)
			return rec[a].xr != rec[b].xr;
		return a < b;
	}
};


int get()
{
	scanf("%d", &n);
	for(last = 0; last < n; ++last){
		scanf("%d %d %d %d", &rec[last].xl, &rec[last].xr, &rec[last].yb, &rec[last].yt);
	}
}

void conquer()
{
	set<int, byBegin> sortByBegin;
	set<int, byEnd> proccesed;
	set<int, byBegin> proccesedBegin;
	int current;
	//Dodaj przetwarzane
	for(int i = 0; i < n; ++i)
		sortByBegin.insert(i);
	int toRemove;
	vector<int> overlapping;
	int t = 0;
	for(set<int, byBegin>::iterator it = sortByBegin.begin(); it != sortByBegin.end();){
		current = *it;
		while(rec[(*proccesed.begin())].xr < rec[(*it)].xl && proccesed.begin() != proccesed.end()){
			toRemove = *proccesed.begin();
			proccesed.erase(proccesed.begin());
		}
		overlapping.clear();
		for(set<int>::iterator iter = proccesed.begin(); iter != proccesed.end(); ++iter){
			if( (rec[*it].yb >= rec[*iter].yt || rec[*it].yt <= rec[*iter].yb) == false)
			{
				overlapping.push_back(*iter);
			}
		}
		if(overlapping.empty() == false){
			sortByBegin.erase(sortByBegin.find(current));
			for(size_t i = 0; i < overlapping.size(); ++i){
				sortByBegin.erase(sortByBegin.find(overlapping[i]));
				rec[*it].yb = min(rec[*it].yb, rec[overlapping[i]].yb);
				rec[*it].xl = min(rec[*it].xl, rec[overlapping[i]].xl);
				rec[*it].yt = max(rec[*it].yt, rec[overlapping[i]].yt);
				rec[*it].xr = max(rec[*it].xr, rec[overlapping[i]].xr);
				
			}
			sortByBegin.insert(current);
			proccesed.clear();
			it = sortByBegin.begin();
		}else{
			proccesed.insert(*it);
			++it;
		}
	}
	printf("%d\n",  sortByBegin.size());
	for(set<int, byBegin>::iterator it = sortByBegin.begin(); it != sortByBegin.end(); it++){
		printf("%d %d %d %d\n", rec[*it].xl, rec[*it].xr, rec[*it].yb, rec[*it].yt);
	}
}



int main()
{
	get();
	conquer();
}