#include<cmath>
#include<queue>
#include<cstdio>
#include<vector>
#include<algorithm>

#define rep(i,n) for(int i=0;i<(n);i++)

using namespace std;

const double EPS=1e-7;

template<class T>
struct point{
	T x,y;
	point operator+(const point &a)const{ return (point){x+a.x,y+a.y}; }
	point operator-(const point &a)const{ return (point){x-a.x,y-a.y}; }
};

template<class T>
point<T> operator*(T c,const point<T> &a){ return (point<T>){c*a.x,c*a.y}; }

bool operator<(const point<double> &a,const point<double> &b){
	return a.x+EPS<b.x || abs(a.x-b.x)<EPS && a.y+EPS<b.y;
}
bool operator==(const point<double> &a,const point<double> &b){
	return abs(a.x-b.x)<EPS && abs(a.y-b.y)<EPS;
}

template<class T>
T dot(const point<T> &a,const point<T> &b){ return a.x*b.x+a.y*b.y; }

template<class T>
T cross(const point<T> &a,const point<T> &b){ return a.x*b.y-a.y*b.x; }

template<class T>
double abs(const point<T> &a){ return sqrt(a.x*a.x+a.y*a.y); }

template<class T>
struct segment{ point<T> a,b; };

enum {CCW=1,CW=-1,ON=0};
int ccw(const point<double> &a,const point<double> &b,const point<double> &c){
	double rdir=cross(b-a,c-a);
	if(rdir> EPS) return CCW;
	if(rdir<-EPS) return CW;
	return ON;
}

template<class T>
double dist(const point<T> &a,const point<T> &b){
	return sqrt((a.x-b.x)*(a.x-b.x)+(a.y-b.y)*(a.y-b.y));
}

bool cover(const segment<double> &S,const point<double> &p){
	return abs(cross(S.a-p,S.b-p))<EPS && dot(S.a-p,S.b-p)<EPS;
}

bool intersect(const segment<double> &S1,const segment<double> &S2){
	if(max(S1.a.x,S1.b.x)+EPS<min(S2.a.x,S2.b.x)
	|| max(S1.a.y,S1.b.y)+EPS<min(S2.a.y,S2.b.y)
	|| max(S2.a.x,S2.b.x)+EPS<min(S1.a.x,S1.b.x)
	|| max(S2.a.y,S2.b.y)+EPS<min(S1.a.y,S1.b.y)) return false;
	return ccw(S1.a,S1.b,S2.a)*ccw(S1.a,S1.b,S2.b)<=0
		&& ccw(S2.a,S2.b,S1.a)*ccw(S2.a,S2.b,S1.b)<=0;
}

point<double> get_intersect(const segment<double> &S1,const segment<double> &S2){
	double a1=cross(S1.b-S1.a,S2.b-S2.a);
	double a2=cross(S1.b-S1.a,S1.b-S2.a);
	if(abs(a1)<EPS){
		if(cover(S1,S2.a)) return S2.a;
		if(cover(S1,S2.b)) return S2.b;
		if(cover(S2,S1.a)) return S1.a;
		return S1.b;
	}
	return S2.a+a2/a1*(S2.b-S2.a);
}

// 追加で頂点集合を指定できるように書き換え
void arrangement(const vector< segment<double> > &S,const vector< point<double> > &plus,vector< point<double> > &P,vector<int> *G){
	int n=S.size();
	P=plus;
	rep(i,n){
		P.push_back(S[i].a);
		P.push_back(S[i].b);
		rep(j,i) if(intersect(S[i],S[j])) P.push_back(get_intersect(S[i],S[j]));
	}
	sort(P.begin(),P.end());
	P.erase(unique(P.begin(),P.end()),P.end());

	rep(i,n){
		vector<int> on;
		rep(u,P.size()) if(cover(S[i],P[u])) on.push_back(u);
		rep(j,(int)on.size()-1){
			int u=on[j],v=on[j+1];
			G[u].push_back(v);
			G[v].push_back(u);
		}
	}
}

int main(){
	int n,m; scanf("%d%d",&n,&m);
	vector< segment<double> > pipe(n);
	rep(i,n) scanf("%lf%lf%lf%lf",&pipe[i].a.x,&pipe[i].a.y,&pipe[i].b.x,&pipe[i].b.y);
	vector< point<double> > stop(m);
	rep(i,m) scanf("%lf%lf",&stop[i].x,&stop[i].y);
	point<double> s,t;
	scanf("%lf%lf%lf%lf",&s.x,&s.y,&t.x,&t.y);

	// 追加の頂点集合
	vector< point<double> > plus=stop;
	plus.push_back(s);
	plus.push_back(t);

	vector< point<double> > P;
	static vector<int> G[100000];
	arrangement(pipe,plus,P,G);

	int N=P.size();
	static bool isstop[100000];
	rep(i,m) rep(u,N) if(P[u]==stop[i]) isstop[u]=true;

	int s_id=find(P.begin(),P.end(),s)-P.begin();
	int t_id=find(P.begin(),P.end(),t)-P.begin();

	// t から stop をまたがずに行ける場所を見つける
	static bool vis[100000];
	vis[t_id]=true;
	queue<int> Q; Q.push(t_id);
	while(!Q.empty()){
		int u=Q.front(); Q.pop();
		rep(i,G[u].size()){
			int v=G[u][i];
			if(!vis[v]){
				vis[v]=true;
				if(!isstop[v]) Q.push(v);
			}
		}
	}

	if(vis[s_id]){ puts("-1"); return 0; }

	double ans=0;
	rep(i,n) ans+=dist(pipe[i].a,pipe[i].b);

	// s から vis を通らずに行ける場所を見つける
	static bool vis2[100000];
	vis2[s_id]=true;
	Q.push(s_id);
	while(!Q.empty()){
		int u=Q.front(); Q.pop();
		rep(i,G[u].size()){
			int v=G[u][i];
			if(!vis2[v]){
				vis2[v]=true;
				if(!vis[v]) Q.push(v);
			}
			if(vis[v]) ans-=dist(P[u],P[v]);   // 一回カウントされる
			else       ans-=dist(P[u],P[v])/2; // 二回カウントされる
		}
	}
	printf("%.9f\n",ans);

	return 0;
}

Measured memory_bytes: 4072