#include <fstream>

using namespace std;
ifstream cin("tribute.in");
ofstream cout("tribute.out");
const int N = 500001;
int x[N], y[N];
int main()
{
    int i, n, dx, dy, cx, cy, sx = 0, sy = 0, d = 0, s = 0, lmin = 1000000, ymin = 1000000, d2 = 0;
    cin >> n >> dx >> dy;
    for(i = 0; i < n; i++)
    {
        cin >> cx >> cy;
        if(cx >= dx)
        {
            sx += cx - dx;
            d++;
        }
        if(cy >= dy)
        {
            sy += cy - dy;
            d2++;
        }
        x[cx]++;
        y[cy]++;
    }
    for(i = 1; i < n - dx; i++)
    {
        s += x[i - 1];
        d -= x[i + dx - 1];
        sx -= d;
        sx += s;
        if(sx < lmin)
            lmin = sx;
    }
    //printf("%d",lmin);
    s = d = 0;
    d = d2;
    for(i = 1; i < n - dy; i++)
    {
        s += y[i - 1];
        d -= y[i + dy - 1];
        sy -= d;
        sy += s;
        if(sy < ymin)
            ymin = sy;
    }
    cout << lmin + ymin;
    return 0;
}