#include <bits/stdc++.h>

using namespace std;

ifstream in("tribute.in");
ofstream out("tribute.out");

int n,x[50001],y[50001],lx,ly;
long long sum;

int main()
{
    in>>n>>lx>>ly;

    for(int i=1;i<=n;i++)
        in>>x[i]>>y[i];

    sort(x+1,x+1+n);
    sort(y+1,y+1+n);

    int st=1,dr=n;

    while(x[dr]-x[st]-lx>0)
        sum+=x[dr--]-x[st++]-lx;

    st=1,dr=n;

    while(y[dr]-y[st]-ly>0)
        sum+=y[dr--]-y[st++]-ly;

    out<<sum;

    return 0;
}