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#pragma GCC optimize("-fdelete-null-pointer-checks,inline-functions-called-once,-funsafe-loop-optimizations,-fexpensive-optimizations,-foptimize-sibling-calls,-ftree-switch-conversion,-finline-small-functions,inline-small-functions,-frerun-cse-after-loop,-fhoist-adjacent-loads,-findirect-inlining,-freorder-functions,no-stack-protector,-fpartial-inlining,-fsched-interblock,-fcse-follow-jumps,-fcse-skip-blocks,-falign-functions,-fstrict-overflow,-fstrict-aliasing,-fschedule-insns2,-ftree-tail-merge,inline-functions,-fschedule-insns,-freorder-blocks,-fwhole-program,-funroll-loops,-fthread-jumps,-fcrossjumping,-fcaller-saves,-fdevirtualize,-falign-labels,-falign-loops,-falign-jumps,unroll-loops,-fsched-spec,-ffast-math,Ofast,inline,-fgcse,-fgcse-lm,-fipa-sra,-ftree-pre,-ftree-vrp,-fpeephole2", 3)
#pragma GCC target("avx", "sse2")
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <iomanip>
#include <vector>
#define maxn 2005
using namespace std;
int T, n, lcnt, pcnt;
double dis[maxn][maxn], ftx, fty;
const double eps = 1e-8;
int sgn(double x) {
if (fabs(x) < eps)
return 0;
return x > 0 ? 1 : -1;
}
struct Point {
double x, y;
Point() {}
Point(double _x, double _y) {
x = _x;
y = _y;
}
Point operator+(const Point &A) {
return Point(x + A.x, y + A.y);
}
Point operator-(const Point &A) {
return Point(x - A.x, y - A.y);
}
double operator^(const Point &A) {
return x * A.y - y * A.x;
}
double operator*(const Point &A) {
return x * A.x + y * A.y;
}
bool operator==(const Point &A) {
return sgn(x - A.x) == 0 && sgn(y - A.y) == 0;
}
bool operator<(Point &A) {
return sgn(x - A.x) == 0 ? y < A.y : x < A.x;
}
double distance(Point v) {
return sqrt((v.x - x) * (v.x - x) + (v.y - y) * (v.y - y));
}
void print() {
printf("[Point] x: %lf, y: %lf\n", x, y);
}
} P[maxn];
struct Line {
Point s, e;
Line() {}
Line(Point _s, Point _e) {
s = _s;
e = _e;
}
int segcrossseg(Line v) {
int d1 = sgn((e - s) ^ (v.s - s));
int d2 = sgn((e - s) ^ (v.e - s));
int d3 = sgn((v.e - v.s) ^ (s - v.s));
int d4 = sgn((v.e - v.s) ^ (e - v.s));
if ((d1 ^ d2) == -2 && (d3 ^ d4) == -2)
return 2;
return (d1 == 0 && sgn((v.s - s) * (v.s - e)) <= 0) ||
(d2 == 0 && sgn((v.e - s) * (v.e - e)) <= 0) ||
(d3 == 0 && sgn((s - v.s) * (s - v.e)) <= 0) ||
(d4 == 0 && sgn((e - v.s) * (e - v.e)) <= 0);
}
Point crosspoint(Line v) {
double a1 = (v.e - v.s) ^ (s - v.s);
double a2 = (v.e - v.s) ^ (e - v.s);
return Point((s.x * a2 - e.x * a1) / (a2 - a1), (s.y * a2 - e.y * a1) / (a2 - a1));
}
bool pointonseg(Point p) {
return sgn((p - s) ^ (e - s)) == 0 && sgn((p - s) * (p - e)) <= 0;
}
bool parallel(Line v) {
return sgn((e - s) ^ (v.e - v.s)) == 0;
}
int relation(Point p) {
int c = sgn((p - s) ^ (e - s));
if (c < 0)
return 1;
else if (c > 0)
return 2;
else
return 3;
}
int linecrossline(Line v) {
if ((*this).parallel(v)) {
return v.relation(s) == 3;
}
return 2;
}
void print() {
printf("[Line] x1: %lf, y1: %lf, x2: %lf, y2:%lf\n", s.x, s.y, e.x, e.y);
}
} L[maxn];
vector<Point> mid;
void build(int source) {
int siz = mid.size();
for (int i = 0; i < siz; i++) {
if (i == source) {
dis[i][i] = 0;
continue;
}
if (sgn(mid[i].x) == 0 || sgn(mid[i].y) == 0 || sgn(mid[i].x - 100) == 0 || sgn(mid[i].y - 100) == 0) {
dis[source][i] = dis[i][source] = 1;
} else {
dis[source][i] = dis[i][source] = 1e9;
}
}
for (int i = 0; i < siz; i++) {
for (int j = 0; j < siz; j++) {
if (i == source || j == source)
continue;
if (i == j)
dis[i][j] = 0;
else {
int flag = 1;
for (int k = 1; k <= lcnt; k++) {
if (Line(mid[i], mid[j]).segcrossseg(L[k]) == 2) {
flag = 0;
break;
}
}
dis[i][j] = flag ? sgn(mid[i].distance(mid[j])) : 1e9;
}
}
}
}
void floyd() {
int siz = mid.size();
for (int k = 0; k < siz; k++)
for (int i = 0; i < siz; i++)
for (int j = 0; j < siz; j++)
dis[i][j] = min(dis[i][j], dis[i][k] + dis[k][j]);
}
double dij[maxn];
int vis[maxn];
void dijkstra(int n, int s) {
for (int i = 0; i <= n; i++)
dij[i] = 1e9, vis[i] = 0;
dij[s] = 0;
for (int i = 0; i <= n; i++) {
int u = 0, mind = 0x3f3f3f3f;
for (int j = 0; j <= n; j++)
if (!vis[j] && dij[j] < mind)
u = j, mind = dij[j];
vis[u] = true;
for (int j = 1; j <= n; j++) {
if (dij[j] > dij[u] + dis[u][j]) {
dij[j] = dij[u] + dis[u][j];
}
}
}
}
bool check_seg(Point A, Point B) {
for (int i = 1; i <= lcnt; i++) {
if (L[i].pointonseg(A) && L[i].pointonseg(B)) {
return true;
}
}
return false;
}
void solve() {
mid.clear();
pcnt = lcnt = 0;
scanf("%d", &n);
P[++pcnt] = Point(0, 0);
P[++pcnt] = Point(0, 100);
P[++pcnt] = Point(100, 100);
P[++pcnt] = Point(100, 0);
L[++lcnt] = Line(P[1], P[2]);
L[++lcnt] = Line(P[2], P[3]);
L[++lcnt] = Line(P[3], P[4]);
L[++lcnt] = Line(P[4], P[1]);
for (int i = 1; i <= n; i++) {
double sx, st, tx, tt;
scanf("%lf %lf %lf %lf", &sx, &st, &tx, &tt);
P[++pcnt] = Point(sx, st);
P[++pcnt] = Point(tx, tt);
L[++lcnt] = Line(P[pcnt], P[pcnt - 1]);
}
scanf("%lf %lf", &ftx, &fty);
for (int i = 1; i <= lcnt; i++) {
for (int j = i + 1; j <= lcnt; j++) {
if (L[i].segcrossseg(L[j]) && L[i].linecrossline(L[j]) == 2) {
P[++pcnt] = L[i].crosspoint(L[j]);
}
}
}
sort(P + 1, P + pcnt + 1);
pcnt = (unique(P + 1, P + pcnt + 1) - P) - 1;
for (int i = 1; i <= pcnt; i++) {
for (int j = 1; j <= pcnt; j++) {
if (i == j)
continue;
int flag = check_seg(P[i], P[j]);
if (!flag)
continue;
for (int k = 1; k <= pcnt; k++) {
if (k == i || k == j)
continue;
if (Line(P[i], P[j]).pointonseg(P[k])) {
flag = 0;
break;
}
}
if (!flag)
continue;
mid.push_back(Point((P[i].x + P[j].x) / 2, (P[i].y + P[j].y) / 2));
}
}
mid.push_back(Point(ftx, fty));
mid.push_back(Point(-1, -1));
sort(mid.begin(), mid.end());
vector<Point>::iterator pos = unique(mid.begin(), mid.end());
mid.erase(pos, mid.end());
int siz = mid.size(), pos1 = -1, pos2 = -1;
for (int i = 0; i < siz; i++) {
if (mid[i] == Point(ftx, fty))
pos1 = i;
if (mid[i] == Point(-1, -1))
pos2 = i;
}
build(pos2);
dijkstra(siz - 1, pos2);
printf("Number of doors = %d\n", (int)(dij[pos1]) - 1);
}
int main(void) {
int T;
scanf("%d", &T);
while(T--){
solve();
if(T) putchar('\n');
}
return 0;
}
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