#include <fstream>
using namespace std;
int n, x, y, i, a, b, minim, sl, sc, conts, contd, contsc, contdc, l[50005], c[50005];
int main()
{
    ifstream f("tribute.in");
    ofstream g("tribute.out");
    f>>n>>x>>y;
    for(i=0;i<n;++i)
    {
        f>>a>>b;
        l[a]++;
        if(a>x)
        {
            sl+=(a-x);
            contd++;
        }
        c[b]++;
        if(b>y)
        {
            sc+=(b-y);
            contdc++;
        }
    }
    minim=sl;
    for(i=x+1;contd;++i)
    {
        sl-=contd;
        contd-=l[i];
        conts+=l[i-x-1];
        sl+=conts;
        minim=min(minim,sl);
    }
    sl=minim;
    minim=sc;
    for(i=y+1;contdc;++i)
    {
        sc-=contdc;
        contdc-=c[i];
        contsc+=c[i-y-1];
        sc+=contsc;
        minim=min(minim,sumc);
    }
    g<<suml+minim<<"\n";
    return 0;
}