#include <bits/stdc++.h>
using namespace std;
ifstream fin ("pachete.in");
ofstream fout ("pachete.out");
/// oooooooof
#define NMAX 50013
int n, v [NMAX], X, Y, A, B;
int LenCadran1, LenCadran2, LenCadran3, LenCadran4;
struct Punct{
    int x;
    int y;
}Cadran [5][NMAX];
bool cmp (Punct A,Punct B){
    if (A.x == B.x)return A.y < B.y;
    return A.x < B.x;
}
int Solve (Punct Cadran [], int LenCadran){
    sort (Cadran + 1, Cadran + LenCadran + 1, cmp);
    int ans = 0;
    for (int i = 1; i <= LenCadran; i ++){
        int temp = 0;
        for (int pas = (1 << 15); pas != 0 ; pas /= 2)
            if (temp + pas <= ans && v [temp + pas] > Cadran [i].y)
                temp += pas;
        temp ++;
        if (temp > ans)v [++ ans] = Cadran [i].y;
        else v [temp] = Cadran [i].y;
    }
    return ans;
}
int main (){
    fin >> n;
    fin >> X >> Y;
    for (int i = 1; i <= n; i ++){
        fin >> A >> B;
        A -= X; B -= Y;
        if (A >= 0 && B >= 0)Cadran [1][++ LenCadran1]     = { A,  B};
        else if (A >= 0 && B < 0)Cadran [2][++ LenCadran2] = { A, -B};
        else if (A < 0 && B < 0)Cadran [3][++ LenCadran3]  = {-A, -B};
        else if (A < 0 && B >= 0)Cadran [4][++ LenCadran4] = {-A,  B};
    }
    fout << Solve (Cadran [1], LenCadran1) + Solve (Cadran [2], LenCadran2) + Solve (Cadran [3], LenCadran3) + Solve (Cadran [4], LenCadran4);
    return 0;
}