#include <bits/stdc++.h>
using namespace std;
ifstream in("pachete.in");
ofstream out("pachete.out");
int solve(vector< pair<int,int> > v)
{
    sort(v.begin(),v.end());
    vector<int> last;
    last.push_back(0);
    int nr = 0;
    for (auto it: v)
    {
        int st = 1, dr = last.size()-1;
        while (st<=dr)
        {
            int mj = (st+dr)/2;
            if (last[mj]<it.second)
                dr = mj-1;
            else
                st = mj+1;
        }
        if (st == (int)last.size())
        {
            nr++;
            last.push_back(it.second);
        }
        else
            last[st] = it.second;
    }
    return nr;
}
int main()
{
    ios::sync_with_stdio(0);
    int n,sx,sy;
    vector<pair<int,int>> v1,v2,v3,v4;
    in >> n >> sx >> sy;
    for (int i = 1; i<=n; i++)
    {
        int x,y;
        in >> x >> y;
        x-=sx; y-=sy;
        if (!x || !y)
            continue;
        if (x<0)
        {
            if (y<0)
                v1.push_back({-x,-y});
            else
                v2.push_back({-x,y});
        }
        else
        {
            if (y<0)
                v3.push_back({x,-y});
            else
                v4.push_back({x,y});
        }
    }
    int ans = 0;
    ans+=solve(v1); ans+=solve(v2); ans+=solve(v3); ans+=solve(v4);
    out << ans;
}