#include <iostream>
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <queue>
#include <memory.h>
using namespace std;
typedef double ld;
const int N=6e2+10;
const ld eps=1e-12;

int dcmp(ld a) {return a<-eps?-1:(a>eps?1:0);}

struct Point {
    ld x,y;
}s,t,a[N];
struct Line {
    Point p,v;
    ld angle;
    int id;
    friend bool operator < (Line a,Line b) {return dcmp(a.angle-b.angle)<0;}
}l[N];
int lcnt;
struct Graph {
    int v,nx;
}g[4*N*N];
int cnt,list[N],dis[N];
bool vis[N];
int T,n;

Point operator + (Point a,Point b) {return (Point){a.x+b.x,a.y+b.y};}
Point operator - (Point a,Point b) {return (Point){a.x-b.x,a.y-b.y};}
Point operator * (Point a,ld b) {return (Point){a.x*b,a.y*b};}
Point operator / (Point a,ld b) {return (Point){a.x/b,a.y/b};}

ld Cross_Multi(Point a,Point b) {return a.x*b.y-a.y*b.x;}
ld Dot_Multi(Point a,Point b) {return a.x*b.x+a.y*b.y;}
Point Mid_Point(Point a,Point b) {return (a+b)/2.0;}
Point Rotate(Point v) {return (Point){-v.y,v.x};}
bool Left(Line l,Point b) {return Cross_Multi(l.v,b-l.p)>0;}

void Add(int u,int v) {
    g[++cnt]=(Graph){v,list[u]};list[u]=cnt;
    g[++cnt]=(Graph){u,list[v]};list[v]=cnt;
}

void Pre_Process(int k) {
    lcnt=0;
    l[++lcnt]=(Line){(Point){0,t.y},(Point){0,-1},atan2(-1,0),n+1};
    l[++lcnt]=(Line){(Point){0,0},(Point){1,0},atan2(0,1),n+1};
    l[++lcnt]=(Line){(Point){t.x,0},(Point){0,1},atan2(1,0),n+1};
    l[++lcnt]=(Line){t,(Point){-1,0},atan2(0,-1),n+1};
    for (int i=1;i<=n;i++)
        if (i!=k) {
            Point mid=Mid_Point(a[i],a[k]),rt=Rotate(a[i]-a[k]);
            l[++lcnt]=(Line){mid,rt,atan2(rt.y,rt.x),i};
        }
    int x=lcnt;
    sort(l+1,l+lcnt+1);
}

Point Linecut(Line a,Line b) {
    Point w=a.p-b.p;
    ld t=Cross_Multi(b.v,w)/Cross_Multi(a.v,b.v);
    return a.p+a.v*t;
}

void Halfcut(int x) {
    deque<Line> q;
    deque<Point> p;
    while (!q.empty()) q.pop_front();
    while (!p.empty()) p.pop_front();
    q.push_front(l[1]);
    for (int i=2;i<=lcnt;i++) {
        while (!p.empty()&&!Left(l[i],p.back())) q.pop_back(),p.pop_back();
        while (!p.empty()&&!Left(l[i],p.front())) q.pop_front(),p.pop_front();
        if (dcmp(Cross_Multi(l[i].v,q.back().v))==0) {
            if (Left(q.back(),l[i].p)) {
                q.pop_back();
                if (!q.empty()) {
                    p.pop_back();
                    p.push_back(Linecut(q.back(),l[i]));
                }
                q.push_back(l[i]);
            }
        }
        else p.push_back(Linecut(q.back(),l[i])),q.push_back(l[i]);
    }
    while (!p.empty()&&!Left(q.front(),p.back())) q.pop_back(),p.pop_back();
    if (p.empty()) return;
    while (!q.empty()) {
        Add(x,q.front().id);
        q.pop_front();
    }
}

void BFS(int v0) {
    queue<int> q;
    memset(dis,0x3f,sizeof dis);memset(vis,0,sizeof vis);
    while (!q.empty()) q.pop();
    q.push(v0);dis[v0]=0;vis[v0]=1;
    while (!q.empty()) {
        int u=q.front();q.pop();
        for (int i=list[u];i;i=g[i].nx)
            if (dis[g[i].v]>dis[u]+1) {
                dis[g[i].v]=dis[u]+1;
                if (!vis[g[i].v]) q.push(g[i].v);
                vis[g[i].v]=1;
            }
        vis[u]=0;
    }
    printf("%d\n",dis[n+1]);
}

int main() {
    for (scanf("%d",&T);T;T--) {
        scanf("%d",&n);
        scanf("%lf%lf%lf%lf",&t.x,&t.y,&s.x,&s.y);
        if (!n) {
            printf("0\n");
            continue;
        }
        int mx=2147483647,st;
        for (int i=1;i<=n;i++) {
            scanf("%lf%lf",&a[i].x,&a[i].y);
            if (mx>Dot_Multi(a[i]-s,a[i]-s)) {
                mx=Dot_Multi(a[i]-s,a[i]-s);
                st=i;
            }
        }
        cnt=0;memset(list,0,sizeof list);
        for (int i=1;i<=n;i++) {
            Pre_Process(i);
            Halfcut(i);
        }
        BFS(st);
    }
}