#include<stdio.h>
#include<algorithm>
#include<iostream>
#define maxn 100050
using namespace std;
int x[maxn],xtot;
int n,a,b,c,d,ans=0;
struct node{
	int x,y,amax;
}ns[maxn];
bool cmp(node a,node b){
	return a.x==b.x ? a.y<b.y : a.x<b.x;
}
void read(){
	scanf("%d",&n);
	scanf("%d %d %d %d",&a,&b,&c,&d);
	for(int i=1;i<=n;i++){
		int x,y;
		scanf("%d %d",&x,&y);
		ns[i].x=x;ns[i].y=y;
	}
	sort(ns+1,ns+n+1,cmp);
}
void solve(){
	for(int i=1;;i++){
		int tmp=ns[i].x;
		xtot++;
		x[xtot]++;
		while(tmp==ns[i+1].x&&i!=n){
			i++;
			x[xtot]++;
		}
		if(i==n)break;
	}
	int tmp=x[0];
	for(int j=2;j<=xtot;j++){
		for(int i=1;i<=x[j];i++){
			for(int k=1;k<=x[j-1];k++){
				if(ns[tmp+i+x[j-1]].y>ns[tmp+k].y){
					ns[tmp+i+x[j-1]].amax=max(ns[tmp+i+x[j-1]].amax,ns[tmp+k].amax+1);
					ans=max(ans,ns[tmp+i+x[j-1]].amax);
				}
			}
		}
		tmp+=x[j-1];
	}
}
int main(){
	freopen("asm_second.in","r",stdin);
	freopen("asm_second.out","w",stdout);
	read();
	solve();
	printf("%d",ans+1);
	return 0;
}