#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ld long double
int c = 0;
struct line{
int x1,x2,y1,y2,id;
line(int x1,int y1,int x2,int y2):x1(x1),y1(y1),x2(x2),y2(y2),id(++c){}
long double operator()(int x) const{
if(x==x2)return (ld)y2;
if(x1==x2)return (ld)y1; // edge case
return (ld)(y2-y1)*(ld)(x-x1)/(ld)(x2-x1) + (ld)y1;
}
bool operator<(const line& other) const{
int pt = max(x1,other.x1);
return this->operator()(pt) < other(pt);
}
bool operator<(const pair<int,int>& other) const{
return this->operator()(other.first) < other.second;
}
};
int32_t main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int N;
cin >> N;
vector<tuple<int,int,int,int>> lines(N);
map<int,vector<int>> removals;
for(auto&[x1,y1,x2,y2]:lines){
cin >> x1 >> y1 >> x2 >> y2;
if(make_pair(x1,y1) > make_pair(x2,y2)){
swap(x1,x2);
swap(y1,y2);
}
}
sort(lines.begin(),lines.end());
map<pair<int,int>,pair<int,int>> opt; // [lidx,ridx] -> (y,x)
set<line> limits;
vector<line> answer;
limits.emplace(-1e8,-1e8,1e8,-1e8);
limits.emplace(-1e8,1e8,1e8,1e8);
opt[{1,2}] = {-1e8,-1e8};
auto findLimits = [&](int x,int y){
int upper = limits.upper_bound(line(x,y,x,y))->id;
int lower = (--limits.upper_bound(line(x,y,x,y)))->id;
return make_pair(lower,upper);
};
for(auto&[x1,y1,x2,y2]:lines){
// process removals
while(removals.begin()!=removals.end() and removals.begin()->first<x1){
for(int&i:removals.begin()->second){
limits.erase(limits.lower_bound(line(removals.begin()->first,i,removals.begin()->first,i))); // figure out how to delete
opt[findLimits(removals.begin()->first,i)]=max(opt[findLimits(removals.begin()->first,i)],{removals.begin()->first,i});
}
removals.erase(removals.begin());
}
// process actually
auto lim = findLimits(x1,y1);
answer.emplace_back(x1,y1,opt[{lim.first,lim.second}].first,opt[{lim.first,lim.second}].second);
// add this to removals if not vertical
auto t = findLimits(x1,y1);
if(x1!=x2){
removals[x2].emplace_back(y2);
// add this to limitations
limits.emplace(x1,y1,x2,y2);
opt[{t.first,c}]={x1,y1};
opt[{c,t.second}]={x1,y1};
} else {
opt[t]={x1,y2};
}
}
for(line&x:answer){
if(x.x2<-1e7)continue;
cout << x.x1 << ' ' << x.y1 << ' ' << x.x2 << ' ' << x.y2 << '\n';
}
}
