Problem: In the International City of Pipe Construction, it is planned to repair the water pipe at a certain point in the water pipe network. The network consists of water pipe segments, stop valves and source point. A water pipe is represented by a segment on a 2D-plane and intersected pair of water pipe segments are connected at the intersection point. A stop valve, which prevents from water flowing into the repairing point while repairing, is represented by a point on some water pipe segment. In the network, just one source point exists and water is supplied to the network from this point.

Of course, while repairing, we have to stop water supply in some areas, but, in order to reduce the risk of riots, the length of water pipes stopping water supply must be minimized. What you have to do is to write a program to minimize the length of water pipes needed to stop water supply when the coordinates of end points of water pipe segments, stop valves, source point and repairing point are given.



Input

A data set has the following format:

> N M
>  xs1 ys1 xd1 yd1
>  ...
>  xsN ysN xdN ydN
>  xv1 yv1
>  ...
>  xvM yvM
>  xb yb
>  xc yc
>

The first line of the input contains two integers, N (1 ≤ N ≤ 300) and M (0 ≤ M ≤ 1,000) that indicate the number of water pipe segments and stop valves. The following N lines describe the end points of water pipe segments. The i-th line contains four integers, xsi, ysi, xdi and ydi that indicate the pair of coordinates of end points of i-th water pipe segment. The following M lines describe the points of stop valves. The i-th line contains two integers, xvi and yvi that indicate the coordinate of end points of i-th stop valve. The following line contains two integers, xb and yb that indicate the coordinate of the source point. The last line contains two integers, xc and yc that indicate the coordinate of the repairing point.

You may assume that any absolute values of coordinate integers are less than 1,000 (inclusive.) You may also assume each of the stop valves, the source point and the repairing point is always on one of water pipe segments and that that each pair among the stop valves, the source point and the repairing point are different. And, there is not more than one intersection between each pair of water pipe segments. Finally, the water pipe network is connected, that is, all the water pipes are received water supply initially.

Output

Print the minimal length of water pipes needed to stop water supply in a line. The absolute or relative error should be less than or 10-6. When you cannot stop water supply to the repairing point even though you close all stop valves, print "`-1`" in a line.

Examples

Input

1 2
0 0 10 0
1 0
9 0
0 0
5 0


Output

9.0


Input

5 3
0 4 2 4
0 2 2 2
0 0 2 0
0 0 0 4
2 0 2 4
0 2
1 0
2 2
1 4
2 1


Output

3.0


Input

2 1
0 0 0 4
0 2 2 2
1 2
0 1
0 3


Output

-1

Solution (in CPP):

Solution:
#include "bits/stdc++.h"
#include<unordered_map>
#pragma warning(disable:4996)
using namespace std;


/* 幾何の基本 */

#include <complex>

typedef long double ld;
typedef complex<ld> Point;
#define REP(i,n) for(int i=0;i<(int)(n);i++)
#define ALL(x) (x).begin(),(x).end()

const ld eps = 1e-12, pi = acos(-1.0);
const ld dtop = pi / 180.;
const ld ptod = 1. / dtop;

namespace std {
	bool operator<(const Point &lhs, const Point &rhs) {
		if (lhs.real() < rhs.real() - eps) return true;
		if (lhs.real() > rhs.real() + eps) return false;
		return lhs.imag() < rhs.imag();
	}
}

// 点の入力
Point input_point() {
	ld x, y;
	cin >> x >> y;
	return Point(x, y);
}

// 誤差つき等号判定
bool eq(const ld a, const ld b) {
	return (abs(a - b) < eps);
}

// 内積
ld dot(const Point& a, const Point& b) {
	return real(conj(a) * b);
}

// 外積
ld cross(const Point& a, const Point& b) {
	return imag(conj(a) * b);
}

// 直線の定義
class Line {
public:
	Point a, b;
	Line() : a(Point(0, 0)), b(Point(0, 0)) {}
	Line(Point a, Point b) : a(a), b(b) {}
	Point operator[](const int _num)const {
		if (_num == 0)return a;
		else if (_num == 1)return b;
		else assert(false);
	}
};

// 円の定義
class Circle {
public:
	Point p;
	ld r;
	Circle() : p(Point(0, 0)), r(0) {}
	Circle(Point p, ld r) : p(p), r(r) {}
};

// CCW
int ccw(const Point& a, const Point &b, const Point &c) {
	const Point nb(b - a);
	const Point nc(c - a);
	if (cross(nb, nc) > eps) return 1;   // a,b,cが反時計周りの順に並ぶ
	if (cross(nb, nc) < -eps) return -1; // a,b,cが時計周りの順に並ぶ
	if (dot(nb, nc) < 0) return 2;       // c,a,bの順に直線に並ぶ
	if (norm(nb) < norm(nc)) return -2;  // a,b,cの順に直線に並ぶ
	return 0;                          // a,c,bの順に直線に並ぶ
}


/* 交差判定 */

// 直線と直線の交差判定
bool isis_ll(const Line& l, const Line& m) {
	return !eq(cross(l.b - l.a, m.b - m.a), 0);
}

// 直線と線分の交差判定
bool isis_ls(const Line& l, const Line& s) {
	return isis_ll(l, s) &&
		(cross(l.b - l.a, s.a - l.a) * cross(l.b - l.a, s.b - l.a) < eps);
}

// 線分と線分の交差判定
bool isis_ss(const Line& s, const Line& t) {
	return ccw(s.a, s.b, t.a) * ccw(s.a, s.b, t.b) <= 0 &&
		ccw(t.a, t.b, s.a) * ccw(t.a, t.b, s.b) <= 0;
}

// 点の直線上判定
bool isis_lp(const Line& l, const Point& p) {
	return (abs(cross(l.b - p, l.a - p)) < eps);
}

// 点の線分上判定
bool isis_sp(const Line& s, const Point& p) {
	return (abs(s.a - p) + abs(s.b - p) - abs(s.b - s.a) < eps);
}

// 垂線の足
Point proj(const Line &l, const Point& p) {
	ld t = dot(p - l.a, l.a - l.b) / norm(l.a - l.b);
	return l.a + t * (l.a - l.b);
}

// 直線と直線の交点
Point is_ll(const Line &s, const Line& t) {
	Point sv = s.b - s.a, tv = t.b - t.a;
	assert(cross(sv, tv) != 0);
	return s.a + sv * cross(tv, t.a - s.a) / cross(tv, sv);
}

// 直線と点の距離
ld dist_lp(const Line& l, const Point& p) {
	return abs(p - proj(l, p));
}

// 直線と直線の距離
ld dist_ll(const Line& l, const Line& m) {
	return isis_ll(l, m) ? 0 : dist_lp(l, m.a);
}

// 直線と線分の距離
ld dist_ls(const Line& l, const Line& s) {
	return isis_ls(l, s) ? 0 : min(dist_lp(l, s.a), dist_lp(l, s.b));
}

// 線分と点の距離
ld dist_sp(const Line& s, const Point& p) {
	Point r = proj(s, p);
	return isis_sp(s, r) ? abs(r - p) : min(abs(s.a - p), abs(s.b - p));
}

// 線分と線分の距離
ld dist_ss(const Line& s, const Line& t) {
	if (isis_ss(s, t)) return 0;
	return min({ dist_sp(s, t.a), dist_sp(s, t.b), dist_sp(t, s.a), dist_sp(t, s.b) });
}


//直線と直線の二等分線のベクトル
Line bisection(const Line &s, const Line &t) {
	const Point laglanju(is_ll(s, t));
	const Point avec = !(abs(laglanju - s[0]))<eps ? s[0] - laglanju : s[1] - laglanju;
	const Point bvec = !(abs(laglanju - t[0]))<eps ? t[0] - laglanju : t[1] - laglanju;

	return Line(laglanju, laglanju + (abs(bvec)*avec + abs(avec)*bvec) / (abs(avec) + abs(bvec)));
}


/* 円 */

// 円と円の交点
vector<Point> is_cc(const Circle& c1, const Circle& c2) {
	vector<Point> res;
	ld d = abs(c1.p - c2.p);
	ld rc = (d * d + c1.r * c1.r - c2.r * c2.r) / (2 * d);
	ld dfr = c1.r * c1.r - rc * rc;
	if (abs(dfr) < eps) dfr = 0.0;
	else if (dfr < 0.0) return res; // no intersection
	ld rs = sqrt(dfr);
	Point diff = (c2.p - c1.p) / d;
	res.push_back(c1.p + diff * Point(rc, rs));
	if (dfr != 0.0) res.push_back(c1.p + diff * Point(rc, -rs));
	return res;
}

// 円と直線の交点
vector<Point> is_lc(const Circle& c, const Line& l) {
	vector<Point> res;
	ld d = dist_lp(l, c.p);
	if (d < c.r + eps) {
		ld len = (d > c.r) ? 0.0 : sqrt(c.r * c.r - d * d); //safety;
		Point nor = (l.a - l.b) / abs(l.a - l.b);
		res.push_back(proj(l, c.p) + len * nor);
		res.push_back(proj(l, c.p) - len * nor);
	}
	return res;
}

// 円と線分の距離
vector<Point> is_sc(const Circle& c, const Line& l) {
	vector<Point> v = is_lc(c, l), res;
	for (Point p : v)
		if (isis_sp(l, p)) res.push_back(p);
	return res;
}

// 円と点の接線
vector<Line> tangent_cp(const Circle& c, const Point& p) {
	vector<Line> ret;
	Point v = c.p - p;
	ld d = abs(v);
	ld l = sqrt(norm(v) - c.r * c.r);
	if (isnan(l)) { return ret; }
	Point v1 = v * Point(l / d, c.r / d);
	Point v2 = v * Point(l / d, -c.r / d);
	ret.push_back(Line(p, p + v1));
	if (l < eps) return ret;
	ret.push_back(Line(p, p + v2));
	return ret;
}

// 円と円の接線
vector<Line> tangent_cc(const Circle& c1, const Circle& c2) {
	vector<Line> ret;
	if (abs(c1.p - c2.p) - (c1.r + c2.r) > -eps) {
		Point center = (c1.p * c2.r + c2.p * c1.r) / (c1.r + c2.r);
		ret = tangent_cp(c1, center);
	}
	if (abs(c1.r - c2.r) > eps) {
		Point out = (-c1.p * c2.r + c2.p * c1.r) / (c1.r - c2.r);
		vector<Line> nret = tangent_cp(c1, out);
		ret.insert(ret.end(), ALL(nret));
	}
	else {
		Point v = c2.p - c1.p;
		v /= abs(v);
		Point q1 = c1.p + v * Point(0, 1) * c1.r;
		Point q2 = c1.p + v * Point(0, -1) * c1.r;
		ret.push_back(Line(q1, q1 + v));
		ret.push_back(Line(q2, q2 + v));
	}
	return ret;
}


/* 多角形 */

typedef vector<Point> Polygon;

// 面積
ld area(const Polygon &p) {
	ld res = 0;
	int n = p.size();
	REP(j, n) res += cross(p[j], p[(j + 1) % n]);
	return res / 2;
}

// 多角形の回転方向
bool is_counter_clockwise(const Polygon &poly) {
	ld angle = 0;
	int n = poly.size();
	REP(i, n) {
		Point a = poly[i], b = poly[(i + 1) % n], c = poly[(i + 2) % n];
		angle += arg((c - b) / (b - a));
	}
	return angle > eps;
}

// 円の内外判定
//  0 => out
//  1 => on
//  2 => in
int is_in_polygon(const Polygon &poly, const  Point& p) {
	ld angle = 0;
	int n = poly.size();
	REP(i, n) {
		Point a = poly[i], b = poly[(i + 1) % n];
		if (isis_sp(Line(a, b), p)) return 1;
		angle += arg((b - p) / (a - p));
	}
	return eq(angle, 0) ? 0 : 2;
}
//円の内外判定2　高速
enum { OUT, ON, IN };
int convex_contains(const Polygon &P, const Point &p) {
	const int n = P.size();
	Point g = (P[0] + P[n / 3] + P[2 * n / 3]) / 3.0l; // inner-point
	int a = 0, b = n;
	while (a + 1 < b) { // invariant: c is in fan g-P[a]-P[b]
		int c = (a + b) / 2;
		if (cross(P[a] - g, P[c] - g) > 0) { // angle < 180 deg
			if (cross(P[a] - g, p - g) > 0 && cross(P[c] - g, p - g) < 0) b = c;
			else                                                  a = c;
		}
		else {
			if (cross(P[a] - g, p - g) < 0 && cross(P[c] - g, p - g) > 0) a = c;
			else                                                  b = c;
		}
	}
	b %= n;
	if (cross(P[a] - p, P[b] - p) < 0) return 0;
	if (cross(P[a] - p, P[b] - p) > 0) return 2;
	return 1;
}

// 凸包
// 点や線を返すことも有り得るので注意
Polygon convex_hull(vector<Point> ps) {
	int n = ps.size();
	int k = 0;
	sort(ps.begin(), ps.end());
	Polygon ch(2 * n);
	for (int i = 0; i < n; ch[k++] = ps[i++])
		while (k >= 2 && ccw(ch[k - 2], ch[k - 1], ps[i]) <= 0) --k;
	for (int i = n - 2, t = k + 1; i >= 0; ch[k++] = ps[i--])
		while (k >= t && ccw(ch[k - 2], ch[k - 1], ps[i]) <= 0) --k;
	ch.resize(k - 1);
	return ch;
}



// 凸カット
vector<Polygon> convex_cut(const Polygon &ps, const Line& l) {
	int n = ps.size();
	Polygon Q;
	Polygon R;
	REP(i, n) {
		Point A = ps[i], B = ps[(i + 1) % n];
		Line m = Line(A, B);
		if (ccw(l.a, l.b, A) != -1) Q.push_back(A);
		if (ccw(l.a, l.b, A) != 1) R.push_back(A);
		if (ccw(l.a, l.b, A) * ccw(l.a, l.b, B) < 0 && isis_ll(l, m)) {
			Q.push_back(is_ll(l, m));
			R.push_back(is_ll(l, m));
		}
	}
	const vector<Polygon>polys{ Q,R };
	return polys;
}


/* アレンジメント */
void add_point(vector<Point> &ps, const Point p) {
	for (Point q : ps) if (abs(q - p) < eps) return;
	ps.push_back(p);
}

typedef double Weight;

struct Edge { int from, to; Weight weight;
int id;
};

typedef vector<Edge> Edges;
typedef vector<Edges> Graph;

void add_edge(Graph &g, const int from, const int to, const Weight weight,const int id) {
	g[from].push_back(Edge{ from, to, weight,id});
}

Graph segment_arrangement(const vector<Line> &s, const vector<pair<Point,bool>> &p) {
	int n = p.size(), m = s.size();
	int id = 0;
	Graph g(n);
	REP(i, m) {
		vector<pair<ld, int>> vec;
		REP(j, n) if (isis_sp(s[i], p[j].first))
			vec.emplace_back(abs(s[i].a - p[j].first), j);
		sort(ALL(vec));
		REP(j, vec.size() - 1) {
			int from = vec[j].second, to = vec[j + 1].second;
			add_edge(g, from, to, abs(p[from].first - p[to].first), id);
			add_edge(g, to, from, abs(p[from].first - p[to].first), id++);
		}
	}
	return g;
}

//Graph sennbunn_arrangement(const vector<Line>&s) {
//	vector<Point>crss;
//	for (int i = 0; i < s.size(); ++i) {
//		for (int j = i + 1; j < s.size(); ++j) {
//			if (isis_ss( s[i],  s[j])) {
//				crss.push_back(is_ll( s[i],  s[j]));
//			}
//		}
//	}
//	for (int i = 0; i <s.size(); ++i) {
//		crss.push_back( s[i][0]);
//		crss.push_back( s[i][1]);
//	}
//	return segment_arrangement(s, crss);
//}

//Graph circle_arrangement(const vector<Circle> &c, const vector<Point> &p) {
//	int n = p.size(), m = c.size();
//	Graph g(n);
//	REP(i, m) {
//		vector<pair<ld, int>> vec;
//		REP(j, n) if (abs(abs(c[i].p - p[j]) - c[i].r) < eps)
//			vec.emplace_back(arg(c[i].p - p[j]), j);
//		sort(ALL(vec));
//		REP(j, vec.size() - 1) {
//			int from = vec[j].second, to = vec[j + 1].second;
//			ld angle = vec[j + 1].first - vec[j].first;
//			add_edge(g, from, to, angle * c[i].r);
//		}
//		if (vec.size() >= 2) {
//			int from = vec.back().second, to = vec.front().first;
//			ld angle = vec.front().first - vec.back().first;
//			add_edge(g, from, to, angle * c[i].r);
//		}
//	}
//	return g;
//}


/* 双対グラフ */

// 線分集合は既にアレンジメントされていなければならない．
// 内側の円は時計回りで，外側の円は反時計回りで得られる．
// 変数 polygon は，vector<int> で表される多角形の集合であり，
// vector<int> で表される 多角形のi番目は，その頂点の頂点集合pにおける番号である．
vector<vector<int>> polygon;
vector<int> seg2p[1024][1024];

//Graph dual_graph(const vector<Line> &s, const vector<Point> &p) {
//	int N = p.size();
//	polygon.clear();
//	REP(i, 1024) REP(j, 1024) seg2p[i][j].clear();
//	vector<vector<tuple<ld, int, bool>>> tup(N);
//	REP(i, s.size()) {
//		int a = -1, b = -1;
//		REP(j, N) if (abs(s[i].a - p[j]) < eps) a = j;
//		REP(j, N) if (abs(s[i].b - p[j]) < eps) b = j;
//		assert(a >= 0 && b >= 0);
//		tup[a].emplace_back(arg(s[i].b - s[i].a), b, false);
//		tup[b].emplace_back(arg(s[i].a - s[i].b), a, false);
//	}
//	REP(i, N) sort(ALL(tup[i]));
//	REP(i, N) {
//		REP(j, tup[i].size()) {
//			ld angle; int pos = j, from = i, to; bool flag;
//			tie(angle, to, flag) = tup[i][j];
//			if (flag) continue;
//			vector<int> ps;
//			while (!flag) {
//				ps.push_back(from);
//				get<2>(tup[from][pos]) = true;
//				seg2p[from][to].push_back(polygon.size());
//				seg2p[to][from].push_back(polygon.size());
//				angle += pi + eps;
//				if (angle > pi) angle -= 2 * pi;
//				auto it = lower_bound(ALL(tup[to]), make_tuple(angle, 0, false));
//				if (it == tup[to].end()) it = tup[to].begin();
//				from = to; tie(angle, to, flag) = *it;
//				pos = it - tup[from].begin();
//			}
//			polygon.push_back(ps);
//		}
//	}
//	Graph g(polygon.size());
//	REP(i, N) REP(j, i) {
//		if (seg2p[i][j].size() == 2) {
//			int from = seg2p[i][j][0], to = seg2p[i][j][1];
//			g[from].push_back(Edge{ from, to });
//			g[to].push_back(Edge{ to, from });
//		}
//	}
//	return g;
//}


/* ビジュアライザ */
const ld zoom = 25;
const ld centerX = 6;
const ld centerY = 5;

void change_color(const int r, const int g, const int b) {
	fprintf(stderr, "c.strokeStyle = 'rgb(%d, %d, %d)';\n", r, g, b);
}

int cordx(Point p) { return 400 + zoom * (p.real() - centerX); }
int cordy(Point p) { return 400 - zoom * (p.imag() - centerY); }

#define cord(p) cordx(p),cordy(p)

void draw_point(const Point& p) {
	fprintf(stderr, "circle(%d, %d, %d)\n", cord(p), 2);
}

void draw_segment(const Line& l) {
	fprintf(stderr, "line(%d, %d, %d, %d)\n", cord(l.a), cord(l.b));
}

void draw_line(const Line& l) {
	Point v = l.b - l.a;
	Line m(l.a - v * Point(1e4, 0), l.b + v * Point(1e4, 0));
	fprintf(stderr, "line(%d, %d, %d, %d)\n", cord(m.a), cord(m.b));
}

void draw_polygon(const Polygon &p) {
	int n = p.size();
	REP(i, n) draw_segment(Line(p[i], p[(i + 1) % n]));
}

void draw_circle(const Circle c) {
	fprintf(stderr, "circle(%d, %d, %d)\n", cord(c.p), (int)(zoom * c.r));
}
int startid;
int goalid;
bool dfs0(const Graph&g,const int now, vector<bool>&came, vector<bool>&close,const vector<bool>&bulbs) {
	came[now] = true;
	for (auto e : g[now]) {
		if (!came[e.to]) {
			if (e.to == startid)return false;
			else {
				if (bulbs[e.to]) {
					close[e.to] = true;
				}
				else {
					if (!dfs0(g, e.to, came, close, bulbs)) {
						return false;
					}
				}
			}
		}
	}
	return true;
}
double dfs1(const Graph&g, const int now, vector<bool>&came,vector<bool>&useedges, const vector<bool>&close) {
	came[now] = true;
	double ans = 0;
	for (auto e : g[now]) {
		if (!useedges[e.id]) {
			ans += e.weight;
			useedges[e.id] = true;
			if (close[e.to])continue;
			else {
				if(!came[e.to])ans += dfs1(g, e.to, came,useedges, close);
			}
		}
	}
	return ans;
}

int main() {
	double sum = 0;
	Graph g;
	int sx, sy, gx, gy;
	Point start;
	Point goal;
	vector<pair<Point, bool>>crss;
	vector<bool>bulbs;
	{
		int N, M; cin >> N >> M;
		vector<Line>ls;
		for (int i = 0; i < N; ++i) {
			int asx, asy, dx, dy; cin >> asx >> asy >> dx >> dy;
			ls.push_back(Line(Point(asx, asy), Point(dx, dy)));
			sum += (abs(Point(asx, asy) - Point(dx, dy)));
		}

		for (int i = 0; i < N; ++i) {
			for (int j = i + 1; j < ls.size(); ++j) {
				bool ok = false;
				for (int k = 0; k < 2; ++k) {
					for (int l = 0; l < 2; ++l) {
						if (ls[i][k] == ls[j][l]) {
							ok = true;
							crss.push_back(make_pair(ls[i][k], false));
							break;
						}

					}
					if (ok)break;
				}
				if (!ok&&isis_ss(ls[i], ls[j])) {
					crss.push_back(make_pair(is_ll(ls[i], ls[j]), false));
				}
			}
		}
		for (int i = 0; i < ls.size(); ++i) {
			crss.push_back(make_pair(ls[i][0], false));
			crss.push_back(make_pair(ls[i][1], false));
		}
		
		vector<Point >bs;
		for (int i = 0; i < M; ++i) {
			int x, y; cin >> x >> y;
			Point p(x, y);
			bs.push_back(p);
		}
		cin >> sx >> sy >> gx >> gy;
		start = Point(sx, sy);
		goal = Point(gx, gy);	
		crss.push_back(make_pair(start, false));
		crss.push_back(make_pair(goal, false));
		sort(crss.begin(), crss.end());
		crss.erase(unique(crss.begin(), crss.end()), crss.end());
		for (int i = 0; i < M; ++i) {
			auto it = find_if(crss.begin(), crss.end(), [=](const pair<Point, bool>&a) {return a.first == bs[i]; });
			if (it == crss.end()) {
				crss.push_back(make_pair(bs[i], true));
			}
			else {
				(*it).second = true;
			}
		}


		for (int i = 0; i < crss.size(); ++i) {
			bulbs.push_back(crss[i].second);
		}
		g= segment_arrangement(ls, crss);
	}
	auto startit = find_if(crss.begin(), crss.end(), [=](const pair<Point, bool>&a) {return a.first == start; });
	startid = startit - crss.begin();
	auto goalit = find_if(crss.begin(), crss.end(), [=](const pair<Point, bool>&a) {return a.first == goal; });
	goalid = goalit - crss.begin();
	vector<bool>close(crss.size(),false);
	vector<bool>came(crss.size(), false);
	if (dfs0(g, goalid, came, close, bulbs)) {
		vector<bool>acame(crss.size(), false);
		vector<bool>useedges(80000, false);
		double ans = dfs1(g, startid, acame, useedges,close);
		cout <<fixed<<setprecision(10)<< sum-ans << endl;
	}
	else {
		cout << -1 << endl;
	}
	return 0;
}