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#include<cstdio>
#include<algorithm>
#include<cassert>
#include<complex>
#include<map>
#include<iomanip>
#include<sstream>
#include<queue>
#include<set>
#include<string>
#include<vector>
#include<iostream>
#include<cstring>
#include<stack>
#include<list>
#define FOR(i, a, b) for(int i =(a); i <=(b); ++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define fup FOR
#define fdo FORD
#define REP(i, n) for(int i = 0;i <(n); ++i)
#define VAR(v, i) __typeof(i) v=(i)
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())
#define siz SZ
#define CLR(x) memset((x), 0, sizeof(x))
#define PB push_back
#define MP make_pair
#define X first
#define Y second 
#define FI X
#define SE Y
#define SQR(a) ((a)*(a))
#define DEBUG 1
#define debug(x) {if (DEBUG)cerr <<#x <<" = " <<x <<endl; }
#define debugv(x) {if (DEBUG) {cerr <<#x <<" = "; FORE(it, (x)) cerr <<*it <<", "; cout <<endl; }}
using namespace std;
typedef long long LL;
typedef long double LD;
typedef pair<int, int>P;
typedef vector<int>VI;
const int INF=1E9+7;
template<class C> void mini(C&a4, C b4){a4=min(a4, b4); }
template<class C> void maxi(C&a4, C b4){a4=max(a4, b4); }
#define DBG(a) a

struct R {int x1; int y1; int x2; int y2;bool removed;
	R():x1(0),y1(0),x2(0),y2(0),removed(false){}
	friend bool operator<(const R& a, const R& b){
		if (a.removed && !b.removed) return false;
		if (!a.removed && b.removed) return true;
	
		if (a.x1>b.x1) return false;
		if (a.x1<b.x1) return true;
		if (a.x2>b.x2) return false;
		if (a.x2<b.x2) return true;
		if (a.y1>b.y1) return false;
		if (a.y1<b.y1) return true;
		if (a.y2>b.y2) return false;
		if (a.y2<b.y2) return true;
		return true;

	}
};

ostream& operator<<(ostream& o, const R& r) {
	o<< r.x1 << ' ' << r.x2 << ' ' << r.y1 << ' ' << r.y2;
	return o;
}

const int MAX_R = 102*1000;
vector<R> r;

typedef pair<pair<int,int>, int> XYI;

struct QT {
	R mybounds;
	QT* subs[4];
	vector<XYI> v;
	void init() {mybounds.x1=-1; mybounds.x2=1000*1010; mybounds.y1=-1; mybounds.y2=1000*1010; subs[0]=subs[1]=subs[2]=subs[3]=0; }

	bool inside(int x, int y) {
		return (x>=mybounds.x1 && x<mybounds.x2 && 
		        y>=mybounds.y1 && y<mybounds.y2);
	}
	bool insert(int x, int y, int i) {
		if (!inside(x,y)) return false;
		if (v.size()<16) {v.PB(MP(MP(x,y),i)); return true;}
		if (subs[0]==NULL) divide();
		FOR(i,0,3) if (subs[i]->insert(x,y,i)); return true;
		return false;
	}

	bool strict_within(int x, int y, const R& a) {
		return (x>a.x1 && x<a.x2 && y>a.y1 && y<a.y2);
	}

	template <typename T> void gather(const R& a, T& res) {
		if (!cross(a, mybounds)) return;
		FORE(i, v) {
			int x = i->FI.FI;
			int y = i->FI.SE;
			if (strict_within(x,y,a)) res.PB(i->SE);
		}
		
		if (subs[0]) FOR(i,0,3) {
			subs[i]->gather(a, res);
		}
	}

	void divide() {
		FOR(i,0,3) subs[i]=new QT;
		R a;
		int x = (mybounds.x2-mybounds.x1)/2+mybounds.x1;
		int y = (mybounds.y2-mybounds.y1)/2+mybounds.y1;
		a.x1=mybounds.x1; a.x2=x;
		a.y1=mybounds.y1; a.y2=y;
		subs[0]->mybounds=a; subs[0]->subs[0]=NULL;

		a.x1=mybounds.x1; a.x2=x;
		a.y1=y; a.y2=mybounds.y2;
		subs[1]->mybounds=a; subs[1]->subs[0]=NULL;

		a.x1=x; a.x2=mybounds.x2;
		a.y1=y; a.y2=mybounds.y2;
		subs[2]->mybounds=a; subs[2]->subs[0]=NULL;

		a.x1=x; a.x2=mybounds.x2;
		a.y1=mybounds.y1; a.y2=y;
		subs[3]->mybounds=a; subs[3]->subs[0]=NULL;
	}

	bool cross(int a1, int a2, int b1, int b2) {
		// czy [a1 .. a2] i [b1..b2] maja czesc wspolna?
		if (a2<=b1 || a1 >= b2) return false; else return true;
		
	}
	bool cross(const R& a, const R& b) {
		return (cross(a.x1,a.x2, b.x1, b.x2) &&
			cross(a.y1,a.y2, b.y1, b.y2));
	}
	list<int> fallinto(const R& a) {
		list<int> l;
//		cerr<<"|";
		FORE(i,r)
			if (!i->removed && cross(a,*i)) {
//				cerr<<i-r.begin()<<'|';
				l.PB(i-r.begin());
			}
		return l;
	}
	void add(int index) {
		insert(r[index].x1,r[index].y1, index);
		insert(r[index].x2,r[index].y1, index);
		insert(r[index].x1,r[index].y2, index);
		insert(r[index].x2,r[index].y2, index);
	}
	void remove(int index) {
	}
};


struct RT {
	list<int> p;
	void remove(int index) {
		FORE(i, p)
			if (*i==index) {
				 p.erase(i); return;
			};
	}
	list<int> iscrossing(int index){
		int iy1 = r[index].y1;
		int iy2 = r[index].y2;
		list<int> res;
		FORE(i, p) {
			int y1=r[*i].y1;
			int y2=r[*i].y2;
			// czy [iy1 .. iy2] i [y1..y2] maja czesc wspolna?
			if (iy2<=y1 || iy1 >= y2) ; else res.PB(*i);
		}
		return res;
	}
	void add(int index) {
		p.PB(index);
	}
};

QT qt;
RT rt;
set<P> ixy;

void remove_r(int index) {
//	usun [index] ze wszystkich struktur: r, rt, ixy, QT;
	rt.remove(index);
	r[index].removed = true;
	// ixy nie trzeba usuwac
	qt.remove(index);
}

void add_r(const R& ar) {
	int index = SZ(r);
	r.PB(ar);
	rt.add(index);
	ixy.insert(MP(ar.x2, index));
	qt.add(index);
	
}

bool isclosing(R& r, int x) {
	return (r.x2 == x);
}

void grow(R& a, const R& b) {
	mini(a.x1,b.x1);
	mini(a.y1,b.y1);
	maxi(a.x2,b.x2);
	maxi(a.y2,b.y2);
}

template <typename A>
R deal_with_intersection(int index, A& li) {
#if 0
	cerr<<"("<<r[index].y1 <<","
	         <<r[index].y2<<"):";
	FORE(j,li)
		cerr<<'['<<r[*j].y1<<','
			 <<r[*j].y2<<']';
#endif
	R super = r[index];
	remove_r(index);
	FORE(j,li) {
		grow(super, r[*j]);
		remove_r(*j);
	}
	
	DBG(cerr<<"<-["<<super<<']';)
	VAR(ki, qt.fallinto(super)); //	DBG(cerr<<'+'<<SZ(ki)<<'+';)
	while(SZ(ki)>0) {
		FORE(k,ki) {
			grow(super, r[*k]);
			remove_r(*k);
		}
		ki = qt.fallinto(super);
	}
	DBG(cerr<<"<-["<<super<<']';)
	return super;
}

void scan() {
	FORE(i,ixy) {
		DBG(cerr<<":";)
		int x = i->FI;
		int index = i->SE;
		if (isclosing(r[index], x))
			rt.remove(index);
		else {
			if (!r[index].removed) {
				DBG(cerr<<"open{"<<x<<"}";)
				VAR(li, rt.iscrossing(index));
				rt.add(index);
				if (!li.empty()) {
					// found intersection
					R ar = deal_with_intersection(index, li);
					add_r(ar);
				}

			}
		}
		DBG(cerr<<endl;)
	}
}

int main(){
	ios_base::sync_with_stdio(false);
	cout << setprecision(15) << fixed;
	int n;
	cin >> n;
	r.reserve(n*2+7);
	//ixy.reserve(n*2+7);
	FOR(i,1,n) {
		R a;
		cin >> a.x1 >> a.x2 >> a.y1 >> a.y2;
		a.x1=a.x1*2+1; a.x2=a.x2*2;
		ixy.insert(MP(a.x1,SZ(r)));
		ixy.insert(MP(a.x2,SZ(r)));
		r.PB(a);
	}
//	qt.construct();
	qt.init();
	scan();
	int count=0;
	FORE(i,r) { i->x1 /= 2; i->x2 /= 2; if (!i->removed) count++;}
	sort(ALL(r));
	cout<<count<<endl;
	FORE(i,r) if (!i->removed) cout<<*i<<endl;
	return 0;
}