#include <fstream>
#include <algorithm>
using namespace std;
ifstream cin("tribute.in");
ofstream cout("tribute.out");
int x[50005],y[50005];
int main()
{
    int n,dx,dy,sol=0;
    cin>>n>>dx>>dy;
    for(int i=1;i<=n;++i)
        cin>>x[i]>>y[i];
    sort(x+1,x+n+1);
    sort(y+1,y+n+1);
    for(int i=1;i<=n;++i)
    {
        sol+=max(x[i+1]-x[n-i]-dx,0);
        sol+=max(y[i+1]-y[n-i]-dy,0);
    }
    cout<<sol;
    return 0;
}