#include<iostream>
#include<cstring>
#include<cstdio>
#include<string>
#include<algorithm>
#include<cmath>
#include<utility>
#include<stdio.h>
#include<cstdlib>
#include<iomanip>	//cout<<setiosflags(ios::fixed)<<setprecision(2);
#include<ctime> //double a=(double)clock();	cout<<a<<endl;
#include<vector>
#include<queue>
using namespace std;
const int MOD=9999997,step=7,muti_x=631,muti_y=1031;
int n,xo,yo,xt,yt,same;
struct hash
{
	int x,y;
}h[10000002];
void insert(int xx,int yy)
{
	int at=(1LL*xx*muti_x+1LL*yy*muti_y)%MOD;
	while(1)
	{
		if(h[at].x==-1&&h[at].y==-1)
			break;
		if(h[at].x==xx&&h[at].y==yy)
			break;
		at+=step;
		if(at>MOD)
			at-=MOD;
	}
	if(h[at].x==xx&&h[at].y==yy)
		same--;
	h[at].x=xx,h[at].y=yy;
	//cout<<same<<endl;
}
void init(){
	for(int i=0;i<=10000000;i++)
		h[i].x=h[i].y=-1;
}
 
int main()
{
	freopen("loverfinding.in","r",stdin);
	freopen("loverfinding.out","w",stdout);
	init();
	scanf("%d%d%d%d%d",&n,&xo,&yo,&xt,&yt);
	for(int i=1;i<=n;i++){
		//cout<<i<<endl;
		int dx,dy;
		scanf("%d%d",&dx,&dy);
		xo+=dx;//
		yo+=dy;//
		if(xo==xt&&yo==yt)break;
		same++;
		insert(xo,yo);
	}
	cout<<same+2<<endl;
	//fclose(stdin),fclose(stdout);
	return 0;
}