#include <fstream>
using namespace std;
ifstream in("tribute.in");
ofstream out("tribute.out");
const int N=50000;
int vfx[N+1],vfy[N+1];
int main()
{
    int n,x,y,i,min1=N+1,a,b,scor=0,min2=N+1;
    in>>n>>x>>y;
    for(i=1; i<=n; ++i)
    {
        in>>a>>b;
        vfx[a]++;
        vfy[b]++;
    }
    int catest=0,catedr=0,cate=0;
    for(i=0; i<x; i++)
        cate+=vfx[i];
    for(; i<=N; i++)
    {
        scor+=vfx[i]*(i-x+1);
        catedr+=vfx[i];
    }
    min1=scor;
    for(i=1; i<=N-x+1; i++)
    {
        catest+=vfx[i-1];
        cate+=vfx[x+i-1];
        scor+=catest;
        scor-=catedr;
        if(scor<min1)
            min1=scor;
        catedr-=vfx[x+i-1];
    }
    catest=0;
    catedr=0;
    cate=0;
    scor=0;
    for(i=0; i<y; i++)
        cate+=vfy[i];
    for(; i<=N; i++)
    {
        scor+=vfy[i]*(i-y+1);
        catedr+=vfy[i];
    }
    min2=scor;
    for(i=1; i<=N-y+1; i++)
    {
        catest+=vfy[i-1];
        cate+=vfy[y+i-1];
        scor+=catest;
        scor-=catedr;
        if(scor<min2)
            min2=scor;
        catedr-=vfy[y+i-1];
    }
    out<<min1+min2;
    return 0;
}