#include<bits/stdc++.h>
#include<set>
#define COGS
using namespace std;
const int maxn=1000010;
typedef pair<int,int> point;
int n,tox,toy,x,y,ans=1,temp1,temp2,cnt;
set <point> s;
point a[maxn];
inline void in(){
	#ifdef COGS
	freopen("loverfinding.in","r",stdin);
	freopen("loverfinding.out","w",stdout);
	#endif
	scanf("%d%d%d%d%d",&n,&x,&y,&tox,&toy);
}
inline void add(int x,int y){
	//s.insert(make_pair(x,y));
	a[++cnt]=make_pair(x,y);
}
inline void deal(){
	add(x,y);
	while (n--){
		scanf("%d%d",&temp1,&temp2);
		x+=temp1,y+=temp2;
		add(x,y);
		if (x==tox&&y==toy) break;
	}
	sort(a+1,a+cnt+1);
	ans=unique(a+1,a+cnt+1)-a-1;
}
inline void p(){
	printf("%d",ans);
}
int Main(){
	in();
	deal();
	p();
	return 0;
}
int main(){;}
int xlm=Main();