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/*	Arek Wróbel - skater
 *
 *	Zadanie: Plemiona
 *	Konkurs: PA2014, runda 5B
 */
#include <cstdio>
#include <algorithm>
#include <cmath>
#include <vector>
using namespace std;
typedef long long LL;
typedef pair<int, int> PII;
typedef vector<int> VI;
#define REP(I, N) for(int I=0; I<(N); ++I)
#define FOR(I, M, N) for(int I=(M); I<=(N); ++I)
#define FORD(I, M, N) for(int I=(M); I>=(N); --I)
#define FOREACH(IT, CON) for(__typeof(CON.begin()) IT=CON.begin(); IT!=CON.end(); ++IT)
#define ST first
#define ND second
#define MP make_pair
#define PB push_back
const int INF=1000000000;
const LL INFLL=1000000000000000000LL;

typedef pair<PII, PII> Rect;
vector<Rect> t;

inline bool przeciecie(Rect a, Rect b) {
	if (a.ST.ND <= b.ST.ST) return false;
	if (b.ST.ND <= a.ST.ST) return false;
	if (a.ND.ND <= b.ND.ST) return false;
	if (b.ND.ND <= a.ND.ST) return false;
	return true;
}

bool make() {  // czy coś zmieniono
	bool wy = false;
	REP(i, (int)t.size()) {
		for (int j = i+1; j<(int)t.size(); ++j) {
			if (przeciecie(t[i], t[j])) {
				wy = true;
				t[i].ST.ST = min(t[i].ST.ST, t[j].ST.ST);
				t[i].ST.ND = max(t[i].ST.ND, t[j].ST.ND);
				t[i].ND.ST = min(t[i].ND.ST, t[j].ND.ST);
				t[i].ND.ND = max(t[i].ND.ND, t[j].ND.ND);
				swap(t[j], t[t.size()-1]);
				t.pop_back();
				--j;
			}
		}
	}
	return wy;
}

int main()
{
	//wej
	int n;
	scanf("%d", &n);
	REP(i, n) {
		int x1, x2, y1, y2;
		scanf("%d%d%d%d", &x1, &x2, &y1, &y2);
		t.PB(MP(MP(x1, x2), MP(y1, y2)));
	}
	//prog
	while (make()) ;
	sort(t.begin(), t.end());
	//wyj
	printf("%d\n", (int)t.size());
	REP(i, (int)t.size())
		printf("%d %d %d %d\n", t[i].ST.ST, t[i].ST.ND, t[i].ND.ST, t[i].ND.ND);
	return 0;
}