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#include <bits/stdc++.h>
using namespace std;
/*
[0 -1]
[1 0]
*/
struct pnt {
int x, y;
pnt (int _x=0, int _y=0) : x(_x), y(_y) {}
void transpose(int a11, int a12, int a21, int a22) {
int temp = x*a11 + y*a12;
y = x*a21 + y*a22;
x = temp;
}
bool operator<(const pnt &p) const {
if (p.x == x) return y < p.y;
return x < p.x;
}
bool operator==(const pnt &p) const {
return (x == p.x && y == p.y);
}
};
struct seg {
pnt st, nd;
seg(pnt p1=pnt(), pnt p2=pnt()) : st(p1), nd(p2) {}
void transpose(int a11, int a12, int a21, int a22) {
st.transpose(a11, a12, a21, a22);
nd.transpose(a11, a12, a21, a22);
}
};
#define HOR_T 0
#define VER_T 1
#define CL_T 2
#define CR_T 3
#define BEG 0
#define END 1
struct event {
int x;
int t;
int i1, i2;
event(int _x, int _t, int _i1, int _i2) : x(_x), t(_t), i1(_i1), i2(_i2) {}
bool operator < (const event &e) const {
if (x == e.x) {
if (t == e.t) return make_pair(i1, i2) < make_pair(e.i1, e.i2);
if (t == HOR_T) return (e.i2 == END);
if (e.t == HOR_T) return (i2 == BEG);
return t < e.t;
}
return x < e.x;
}
};
inline void swap(pnt &p1, pnt &p2) {
swap(p1.x, p2.x);
swap(p1.y, p2.y);
}
vector<seg> segments;
vector<pnt> result;
vector<pnt> temp_res;
vector<event> events;
map<int, int> hor;
map<int, int> cl;
map<int, int> cr;
void read() {
int n;
scanf("%d", &n);
segments.resize(n);
for (int i = 0; i < n; i++) {
cin >> segments[i].st.x >> segments[i].st.y >> segments[i].nd.x >> segments[i].nd.y;
}
}
void rotate(int a11, int a12, int a21, int a22) {
for (auto s: segments) {
s.transpose(a11, a12, a21, a22);
}
}
void solve_prob() {
temp_res.clear();
events.clear();
hor.clear(); cl.clear(); cr.clear();
for (auto s: segments) {
if (s.st.x > s.nd.x) swap(s.st, s.nd);
if (s.st.x == s.nd.x) {
if (s.st.y > s.nd.y) swap(s.st, s.nd);
events.push_back(event(s.st.x, VER_T, s.st.y, s.nd.y));
}
else if (s.st.y == s.nd.y) {
events.push_back(event(s.st.x, HOR_T, s.st.y, BEG));
events.push_back(event(s.nd.x, HOR_T, s.st.y, END));
}
else if (s.st.y - s.nd.y < 0) {
events.push_back(event(s.st.x, CR_T, s.st.y, BEG));
events.push_back(event(s.nd.x, CR_T, s.nd.y, END));
}
else {
events.push_back(event(s.st.x, CL_T, s.st.y, BEG));
events.push_back(event(s.nd.x, CL_T, s.nd.y, END));
}
}
sort(events.begin(), events.end());
for (auto e: events) {
if (e.t == VER_T) {
auto it = hor.lower_bound(e.i1);
while (it != hor.end() && it->first <= e.i2) {
temp_res.push_back({e.x, it->first});
it++;
}
it = cr.lower_bound(e.i1 - e.x);
while (it != cr.end() && it->first <= e.i2 - e.x) {
temp_res.push_back({e.x, it->first + e.x});
it++;
}
it = cl.lower_bound(e.i1 + e.x);
while (it != cl.end() && it->first <= e.i2 + e.x) {
temp_res.push_back({e.x, it->first - e.x});
it++;
}
}
if (e.t == CR_T) {
if (e.i2 == BEG) cr[e.i1 - e.x]++;
else if (--cr[e.i1 - e.x] <= 0) cr.erase(e.i1 - e.x);
}
if (e.t == CL_T) {
if (e.i2 == BEG) cl[e.i1 + e.x]++;
else if (--cl[e.i1 + e.x] <= 0) cl.erase(e.i1);
}
if (e.t == HOR_T) {
if (e.i2 == BEG) hor[e.i1]++;
else if (--hor[e.i1] <= 0) hor.erase(e.i1);
}
}
}
void add_to_res(int a11, int a12, int a21, int a22) {
for (auto p: temp_res) {
p.transpose(a11, a12, a21, a22);
result.push_back(p);
}
}
void solve() {
solve_prob();
for (auto &p: temp_res) {
p.x *= 2; p.y *= 2;
}
add_to_res(1, 0, 0, 1);
for (auto &p: temp_res) {
p.x /= 2; p.y /= 2;
}
rotate(1, -1, 1, 1);
solve_prob();
add_to_res(1, 1, -1, 1);
rotate(1, 1, -1, 1);
for (auto &p: temp_res) {
p.x /= 2; p.y /= 2;
}
sort(result.begin(), result.end());
result.erase(unique(result.begin(), result.end()), result.end());
for (auto p : result) {
cout << p.x/2 << "." << (p.x % 2 == 1 ? "5" : "0") << " ";
cout << p.y/2 << "." << (p.y % 2 == 1 ? "5" : "0") << "\n";
}
}
int main() {
read();
solve();
}
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