#include <bits/stdc++.h>
#define nmax 50002
#define ll long long
using namespace std;
ifstream fin("tribute.in");
ofstream fout("tribute.out");
int X[nmax], Y[nmax];
int x, y;
int n, dx, dy;
int i;
void afis(int *a, int n)
{
    for(int i = 0; i <= n; i++)
        cout << a[i] << " ";
    cout << "\n";
}
ll Sol(int *A, int D)
{
    int cnt = A[0];
    ll ds[nmax], dd[nmax];
    ds[0] = 0;
    int i;
    for(i = 1; i < nmax; i++)
    {
        ds[i] = cnt + ds[i - 1];
        cnt += A[i];
    }
    dd[nmax - 1] = 0;
    cnt = A[nmax - 1];
    for(i = nmax - 2; i >= 0; i--)
    {
        dd[i] = cnt + dd[i + 1];
        cnt += A[i];
    }
    ll DIST, minDIST = LLONG_MAX;
    for(i = 0; i < nmax; i++)
    {
        if(i >= D)
        {
            DIST = ds[i - D] + dd[i];
            minDIST = min(minDIST, DIST);
        }
        if(i < nmax - D)
        {
            DIST = ds[i] + dd[i + D];
            minDIST = min(minDIST, DIST);
        }
    }
    return minDIST;
}
int main()
{
    fin >> n >> dx >> dy;
    for(i = 1; i <= n; i++)
    {
        fin >> x >> y;
        X[x]++;
        Y[y]++;
    }
    fout << Sol(X, dx) + Sol(Y, dy) << "\n";
    return 0;
}