#include <bits/stdc++.h>

using namespace std;
ifstream in("tribute.in");
ofstream out("tribute.out");
int ox[50001];
int oy[50001];
int main()
{
    int x,y,n,i,j,dx,dy,ans=0;
    in>>n>>dx>>dy;
    for(i=1;i<=n;i++)
    {
        in>>x>>y;
        ox[i]=x;
        oy[i]=y;
    }
    sort(ox+1,ox+n+1);
    sort(oy+1,oy+n+1);
    for(i=1;i<=n;i++)
    {
        ans+=max(0,ox[i+1]-ox[n-i]-dx);
        ans+=max(0,oy[i+1]-oy[n-i]-dy);
    }
    out<<ans;
    return 0;
}