#include <fstream.h>
#include <math.h>
int main()
{
int n,i,j,nr=0,ok;
long x,y,xi,yi;
char a[31500][2];

ifstream f("pachete.in");
ofstream g("pachete.out");
f>>n>>x>>y;
for (i=0;i<n;i++)
    {
    f>>xi>>yi;
    a[i][0]=xi+'0';
    a[i][1]=yi+'0';
    if (i>0)
       {ok=1;
       for (j=0;j<i;j++)
	   {
	   if ((abs(x-xi)+abs(y-yi))!=(abs(xi-(a[j][0]-'0'))+abs(yi-(a[j][1]-'0')))+(abs(x-(a[j][0]-'0'))+abs(y-(a[j][1]-'0'))))
	       ok=0;
	   }
       if (!ok) nr++;
       }
    }
g<<nr<<'\n';
f.close();
g.close();
return 0;
}