#include <fstream>

using namespace std;
ifstream in("tribute.in");
ofstream out("tribute.out");
int l[50005], c[50005];
int main()
{
    int n, x, y, i, a, b, minim, sl=0, sc=0, conts=0, contd=0, contsc=0, contdc=0;
    in>>n>>x>>y;
    for(i=0; i<n; i++)
    {
        in>>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,sc);
    }
    out<<sl+minim;
    return 0;
}