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#include <vector>
#include <iostream>
#include <sstream>
#include <math.h>
#include <sys/time.h>
#include <cstdlib>
#include <algorithm>
#include <cassert>
#include <cstring>
#include <fstream>
#include <set>

#define FOR(i,a,b)  for(__typeof(b) i=(a);i<(b);++i)
#define REP(i,a)    FOR(i,0,a)
#define FOREACH(x,c)   for(__typeof(c.begin()) x=c.begin();x != c.end(); x++)
#define ALL(c)      c.begin(),c.end()
#define CLEAR(c)    memset(c,0,sizeof(c))
#define SIZE(c) (int) ((c).size())

#define PB          push_back
#define MP          make_pair
#define X           first
#define Y           second

#define ULL         unsigned long long
#define LL          long long
#define LD          long double
#define II         pair<int, int>
#define DD         pair<double, double>

#define VC	    vector
#define VI          VC<int>
#define VVI         VC<VI>
#define VD          VC<double>
#define VS          VC<string>
#define VII         VC<II>
#define VDD         VC<DD>

#define DB(a)       cerr << #a << ": " << a << endl;

using namespace std;

template<class T> void print(VC < T > v) {cerr << "[";if (SIZE(v) != 0) cerr << v[0]; FOR(i, 1, SIZE(v)) cerr << "," << v[i]; cerr << "]\n";}
template<class T> string i2s(T &x) { ostringstream o; o << x; return o.str(); }
VS split(string &s, char c = ' ') {VS all; int p = 0, np; while (np = s.find(c, p), np >= 0) {if (np != p) all.PB(s.substr(p, np - p)); p = np + 1;} if (p < SIZE(s)) all.PB(s.substr(p)); return all;}

typedef pair<II,II> Rect; 

inline LL area(const Rect &r){
    return ((LL)(r.X.Y-r.X.X))*(r.Y.Y-r.Y.X);
}

inline int isect(const II &i1, const II &i2){
    return (i1.Y > i2.X && i2.Y > i1.X);
}

inline int isect(const Rect &r1, const Rect &r2){
    return (isect(r1.X,r2.X) && isect(r1.Y,r2.Y));
}

inline II unite(const II &i1, const II &i2){
    return MP(min(i1.X,i2.X),max(i1.Y,i2.Y));
}

int n;
VC<Rect> R;

void readData(){
    scanf("%d",&n);
    R.resize(n);
    REP(i,n)
        scanf("%d%d%d%d",&(R[i].X.X),&(R[i].X.Y),&(R[i].Y.X),&(R[i].Y.Y));     
}

void writeResult(){
    sort(ALL(R));
    printf("%d\n",SIZE(R));
    REP(i,n)
        printf("%d %d %d %d\n",R[i].X.X,R[i].X.Y,R[i].Y.X,R[i].Y.Y);     
}

int areaDec(const Rect &r1, const Rect &r2){
    return area(r1) > area(r2);
}

VI removed;

void solveBrute(){
    sort(ALL(R),areaDec);
    bool ok = false;
    VI remove;
    removed = VI(n,0);
    do{
        ok = false;
        remove.clear();
        n = SIZE(R);
        REP(i,n) if (!removed[i]){
           FOR(j,i+1,n) if (!removed[j]){
                if(isect(R[i],R[j])){
                    R[i].X = unite(R[i].X,R[j].X);
                    R[i].Y = unite(R[i].Y,R[j].Y);
                    remove.PB(j);
                    removed[j] = 1;
                    ok = true;
                }
            }
        }
        int i = 0, j = 0, k = 0;
        sort(ALL(remove));
        remove.PB(-1); // sentry
        while (i < n){
            if (i == remove[k]){
                removed[i] = 0;
                i++;
                k++;
            } else{
                R[j] = R[i];
                i++; j++;
            }
        }
        //DB(k);
        //cerr << SIZE(remove) << endl;
        R.resize(j);
    }while(ok);
}

int main(int argc, char *argv[]){
    readData();
    solveBrute();
    writeResult();
    return 0;
}