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// PA2014, runda 5, Plemiona
// Andrzej Pezarski

#include <cstdio>
#include <cstdlib>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <algorithm>

using namespace std;

int N, L;
bool odwroc;


priority_queue<pair<int, int> > Q;

vector<int> X, Y;
vector<pair<pair<int, int>,pair<int, int> > > P;
vector<bool> taken;


vector<set<pair<int, int> > > A, B;


inline void doCheck(set<pair<int, int> > &S, vector<int> &Res, pair<int, int> x) {
	auto tmp1=make_pair(1+2*x.first, -10000000);
	auto tmp2=make_pair(2*x.second, -10000000);
	for (auto it=S.lower_bound(tmp1), end=S.lower_bound(tmp2); it!=end; ++it) {
//			printf("tutaj\n");
		if (taken[it->second]) {
			Res.push_back(it->second);
			taken[it->second]=false;
		}
	}
}

vector<int> check(pair<int, int> x, pair<int, int> y) {
	vector<int> Res;
	int l=lower_bound(Y.begin(), Y.end(), y.first)-Y.begin()+L;
	int r=lower_bound(Y.begin(), Y.end(), y.second)-Y.begin()+L-1;
	
	doCheck(A[l], Res, x);
	doCheck(A[r], Res, x);
	doCheck(B[l], Res, x);
	doCheck(B[r], Res, x);
	while(l/2!=r/2) {
		if (l%2==0) {
			doCheck(A[l+1], Res, x);
			doCheck(B[l+1], Res, x);
		}
		if (r%2==1) {
			doCheck(A[r-1], Res, x);
			doCheck(B[r-1], Res, x);
		}
		l/=2;
		r/=2;
		doCheck(A[l], Res, x);
		doCheck(A[r], Res, x);
	}
	while(l>1) {
		l/=2;
		doCheck(A[l], Res, x);
	}
	return Res;
}

inline void doWsadz(set<pair<int, int> > &S, pair<int, int> x, int v) {
	S.insert(make_pair(1+2*x.first, v));
	S.insert(make_pair(2*x.second, v));
}

void wsadz(pair<int, int> x, pair<int, int> y, int v) {
	int l=lower_bound(Y.begin(), Y.end(), y.first)-Y.begin()+L;
	int r=lower_bound(Y.begin(), Y.end(), y.second)-Y.begin()+L-1;
	
	doWsadz(A[l], x, v);
	doWsadz(A[r], x, v);
//		doWsadz(B[l], x, v);
//		doWsadz(B[r], x, v);
	while(l/2!=r/2) {
		if (l%2==0) {
			doWsadz(A[l+1], x, v);
//			doWsadz(B[l+1], x, v);
		}
		if (r%2==1) {
			doWsadz(A[r-1], x, v);
//			doWsadz(B[r-1], x, v);
		}
		l/=2;
		r/=2;
		doWsadz(B[l], x, v);
		doWsadz(B[r], x, v);
	}
	while(l>1) {
		l/=2;
		doWsadz(B[l], x, v);
	}
}

inline void doUsun(set<pair<int, int> > &S, pair<int, int> x, int v) {
	S.erase(make_pair(1+2*x.first, v));
	S.erase(make_pair(2*x.second, v));
}

void usun(pair<int, int> x, pair<int, int> y, int v) {
	int l=lower_bound(Y.begin(), Y.end(), y.first)-Y.begin()+L;
	int r=lower_bound(Y.begin(), Y.end(), y.second)-Y.begin()+L-1;
	
	doUsun(A[l], x, v);
	doUsun(A[r], x, v);
//		doUsun(B[l], x, v);
//		doUsun(B[r], x, v);
	while(l/2!=r/2) {
		if (l%2==0) {
			doUsun(A[l+1], x, v);
//			doUsun(B[l+1], x, v);
		}
		if (r%2==1) {
			doUsun(A[r-1], x, v);
//			doUsun(B[r-1], x, v);
		}
		l/=2;
		r/=2;
		doUsun(B[l], x, v);
		doUsun(B[r], x, v);
	}
	while(l>1) {
		l/=2;
		doUsun(B[l], x, v);
	}
}

int main() {
	
	//INPUT
	
	scanf("%d", &N);
	P.resize(N);
	taken.resize(N);
	for(int i=0; i<N; i++) taken[i]=false;
	for(auto &p:P) {
		scanf("%d%d%d%d", &p.first.first, &p.first.second, &p.second.first, &p.second.second);
		X.push_back(p.first.first);
		X.push_back(p.first.second);
		Y.push_back(p.second.first);
		Y.push_back(p.second.second);
	}
	sort(X.begin(), X.end());
	X.resize(unique(X.begin(), X.end())-X.begin());
	sort(Y.begin(), Y.end());
	Y.resize(unique(Y.begin(), Y.end())-Y.begin());
	odwroc=(X.size()<Y.size());
	if(odwroc) {
		X.swap(Y);
		for(auto &p:P) swap(p.first, p.second);
	}
	
	L=1; while (L<=int(Y.size())) L*=2;
	A.resize(2*L);
	B.resize(2*L);

	// GO
	
	for (int i=0; i<N; i++) Q.push(make_pair(P[i].first.first-P[i].first.second, i));
	while (!Q.empty()) {
		int v=Q.top().second; Q.pop();
		auto X=check(P[v].first, P[v].second);
		if (X.empty()) {
			wsadz(P[v].first, P[v].second, v);
			taken[v]=true;
		} else {
			int x1=P[v].first.first, x2=P[v].first.second, y1=P[v].second.first, y2=P[v].second.second;
			for (auto x:X) {
				x1=min(x1, P[x].first.first);
				x2=max(x2, P[x].first.second);
				y1=min(y1, P[x].second.first);
				y2=max(y2, P[x].second.second);
				usun(P[x].first, P[x].second, x);
				taken[x]=false;
			}
			P[v].first.first=x1, P[v].first.second=x2, P[v].second.first=y1, P[v].second.second=y2;
			Q.push(make_pair(P[v].first.first-P[v].first.second, v));
		}
	}
	
	// OUTPUT
	
	vector<pair<pair<int, int>,pair<int, int> > > Res;
	for(int i=0; i<N; i++) {
		if (taken[i]) {
			Res.push_back(P[i]);
		}
	}
	
	if (odwroc) {
		for(auto &p:Res) swap(p.first, p.second);
	}
	sort(Res.begin(), Res.end());
	printf("%d\n", int(Res.size()));
	for(auto &p:Res) {
		printf("%d %d %d %d\n", p.first.first, p.first.second, p.second.first, p.second.second);
	}
	
	return 0;
}