#include <stdio.h>
#include <set>
#include <algorithm>

using namespace std;

#define maxn 50010

set <int> s;
set <int> :: iterator I;
int n,px,py,l,sol;
int a[maxn],b[maxn];
int x[maxn],y[maxn];
int p[maxn];

int cmp(int i,int j)
{
    return ((x[i]<x[j]) || ((x[i]==x[j]) && (y[i]<y[j])));
}

void solve()
{
    int i; 
    
    sort(p+1,p+l+1,cmp);    
     
    for (i=l;i>0;i--)
    {
        I = s.upper_bound(y[p[i]]);
        if (I == s.end()) sol++;
        else s.erase(I);
        s.insert(y[p[i]]);        
    }
    
    s.clear();
}

int main()
{
    freopen("pachete.in","r",stdin);
    freopen("pachete.out","w",stdout);
    
    int i;
    
    scanf("%d ",&n);
    scanf("%d %d ",&px,&py);
    
    for (i=1;i<=n;i++) scanf("%d %d",&a[i],&b[i]);
    
    l=0;
    for (i=1;i<=n;i++) 
      if ((a[i]>px) && (b[i]>py)) 
      {
          l++;
          x[l]=a[i];
          y[l]=b[i];
          p[l]=l;
      }
      
    solve();
    
    l=0;
    for (i=1;i<=n;i++)
      if ((a[i]>px) && (b[i]<py))
      {
          l++;
          x[l]=a[i];
          y[l]=py-b[i];
          p[l]=l; 
      }
      
    solve();

    l=0;
    for (i=1;i<=n;i++)
      if ((a[i]<px) && (b[i]<py))
      {
          l++;
          x[l]=px-a[i];
          y[l]=py-b[i];
          p[l]=l; 
      }
      
    solve();
    
    l=0;
    for (i=1;i<=n;i++)
      if ((a[i]<px) && (b[i]>py))
      {
          l++;
          x[l]=px-a[i];
          y[l]=b[i];
          p[l]=l; 
      }
      
    solve();  
    printf("%d\n",sol);
      
    return 0;
}