#include <iostream>

#include <cstdio>

#include <cstring>

#include <algorithm>

using namespace std;

const double eps=0.000000001;

struct point{

	double x,y;

}Point[100],des;

struct edge{

	point start,end;

}Edge[100],Tmp;

int ne,np;

double multi(point p1,point p2, point p0){

    return (p1.x-p0.x)*(p2.y-p0.y)-(p2.x-p0.x)*(p1.y-p0.y);

}

bool cross(edge v1, edge v2){

    if(max(v1.start.x,v1.end.x)>=min(v2.start.x,v2.end.x)&&

    max(v2.start.x,v2.end.x)>=min(v1.start.x,v1.end.x)&&

    max(v1.start.y,v1.end.y)>=min(v2.start.y,v2.end.y)&&

    max(v2.start.y,v2.end.y)>=min(v1.start.y,v1.end.y)&&

    multi(v2.start,v1.end,v1.start)*multi(v1.end,v2.end,v1.start)>eps&&

    multi(v1.start,v2.end,v2.start)*multi(v2.end,v1.end,v2.start)>eps)

    return true;

    return false;

}

int main(){

	while(scanf("%d",&ne)!=EOF){

		np=0;

		for(int i=0;i<ne;i++){

			scanf("%lf%lf",&Point[np].x,&Point[np].y);

			np++;

			scanf("%lf%lf",&Point[np].x,&Point[np].y);

			np++;

			Edge[i].start=Point[np-2]; Edge[i].end=Point[np-1];

		}

		Point[np].x=0; Point[np].y=0;

		np++;

		Point[np].x=0; Point[np].y=100;

		np++;

		Point[np].x=100; Point[np].y=0;

		np++;

		Point[np].x=100; Point[np].y=100;

		np++;

		scanf("%lf%lf",&des.x,&des.y);

		int ans=1000,tmp;

		for(int i=0;i<np;i++){

			Tmp.start=des; Tmp.end=Point[i]; tmp=0;

			for(int i=0;i<ne;i++){

				if(cross(Tmp,Edge[i]))

				tmp++;

			}

			ans=min(ans,tmp);

		}

		printf("Number of doors = %d\n",ans+1);

	}

}