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#include <iostream>
#include <cstdio>
#include <algorithm>
using namespace std;
	
struct Rectangle{
	int x1;
	int x2;
	int y1;
	int y2;
};

struct Event{
	int x;
	int y;
	int type;
};

void doStuff_Y(int a,int b,int x);
void mcount(int p,int q,char prio);

int nbr; int nbr2;
Event* E;
Rectangle* R;

bool oper1(Event e1, Event e2){
	if(e1.y==e2.y)return(e1.type<e2.type);
	return (e1.y<e2.y);
}
bool oper2(Event e1, Event e2){
	if(e1.x==e2.x)return(e1.type<e2.type);
	return (e1.x<e2.x);
}

void doStuff_X(int a,int b,int x){
//	cout<<"XXXXXXXX "<<a<<"  -  "<<b<<endl;
	if(a==b)return;
	int sum=0;
	sort(E+a,E+b,oper2);
	for(int i=a;i<b-2;i++){
//		cout<<"       X "<<i<<"  sum = "<<sum<<"  E="<<E[i].x<<","<<E[i].y<<" t"<<E[i].type<<endl;
		sum=sum+E[i].type;
		if(sum==0){
			nbr++;
		//	doStuff_Y(a,i+1,0);
		//	doStuff_Y(i+1,b,0);
		//	cout<<"return to X "<<a<<"-"<<b<<endl;
			mcount(a,i+1,'y');
			mcount(i+1,b,'y');
			return;
		}
	}
	
//	if(x==0){ doStuff_Y(a,b,1);}
//	if(x==1)nbr++;
}

/*
3
1 2 1 2
3 4 4 5
5 6 1 2

*/
void doStuff_Y(int a,int b,int x){
//	cout<<"YYYYYYYY "<<a<<"  -  "<<b<<endl;
	
	if(a==b)return;
	int sum=0;
	sort(E+a,E+b,oper1);
	for(int i=a;i<b-2;i++){
//		cout<<"       Y "<<i<<"  sum = "<<sum<<"  E="<<E[i].x<<","<<E[i].y<<" t"<<E[i].type<<endl;
		sum=sum+E[i].type;
		if(sum==0){
			nbr++;
			//doStuff_X(a,i+1,0);
			//doStuff_X(i+1,b,0);
			//cout<<"return to Y "<<a<<"-"<<b<<endl;
			mcount(a,i+1,'x');
			mcount(i+1,b,'x');
			return;
		}
	}
	
//	if(x==0){ doStuff_X(a,b,1);}
//	if(x==1)nbr++;
}


void mcount(int p,int q,char prio){
//	cout<<"                      count : "<<p<<"  *  "<<q<<endl;
	int tmpnbr=nbr;
	if(prio='x'){
		doStuff_X(p,q,0);
		if(nbr-tmpnbr==0)doStuff_Y(p,q,0);
		
	}else{
		doStuff_Y(p,q,0);
		if(nbr-tmpnbr==0)doStuff_X(p,q,0);
	}
	if(nbr-tmpnbr==0){
//cout<<"####### : "<<p<<"  *  "<<q<<endl;
		int minx=E[p].x;
		int maxx=E[p].x;
		int miny=E[p].y;
		int maxy=E[p].y;
		for(int i=p;i<q;i++){
//cout<<"---------------->  x="<<E[i].x<<" y="<<E[i].y<<"      ;"<<minx<<" "<<maxx<<" "<<miny<<" "<<maxy<<endl;			
			if(minx>E[i].x)minx=E[i].x;
			if(maxx<E[i].x)maxx=E[i].x;
			if(miny>E[i].y)miny=E[i].y;
			if(maxy<E[i].y)maxy=E[i].y;
		}
		R[nbr2].x1=minx;
		R[nbr2].x2=maxx;
		R[nbr2].y1=miny;
		R[nbr2].y2=maxy;
		nbr2++;
	}
}
	

int main(){
	int n; 
	scanf("%d",&n);
/*	int* X1=new int[n];
	int* X2=new int[n];
	int* Y1=new int[n];
	int* Y2=new int[n];*/
	int a,b,c,d; 
	E=new Event[n];
	R=new Rectangle[n];
	
	for(int i=0;i<2*n;i=i+2){
	//	scanf("%d %d %d %d",&X1[i],&X2[i],&Y1[i],&Y2[i]);
	//	scanf("%d %d %d %d",&R[i].x1,&R[i].x2,&R[i].y1,&R[i].y2);
		scanf("%d %d %d %d",&a,&b,&c,&d);
		E[i].x=a;
		E[i].y=c;
		E[i].type=1;
		E[i+1].x=b;
		E[i+1].y=d;
		E[i+1].type=-1;
	}
	
	//sort(E+0,E+2*n,oper1);
	//for(int i=0; i<2*n;i++)cout<<E[i].x<<" "<<E[i].y<<"  "<<E[i].type<<endl;
	
	
	nbr=0; nbr2=0;
	
	//doStuff_Y(0,2*n,0);
	//doStuff_X(0,2*n,0);
	mcount(0,2*n,'x');
	nbr++;
//	cout<<"           RESULT= "<<nbr<<"   2->"<<nbr2<<endl;
	printf("%d\n",nbr);
	for(int i=0;i<nbr2;i++){
		printf("%d %d %d %d\n",R[i].x1,R[i].x2,R[i].y1,R[i].y2);
	}
	
//cin>>n;
	return 0;
}