#include <fstream>
#include <algorithm>
using namespace std;
ifstream fi("tribute.in");
ofstream fo("tribute.out");
int n,i,a,b,x[50001],y[50001],s;
int main()
{fi>>n>>a>>b;
for(i=1;i<=n;i++) fi>>x[i]>>y[i];
sort(x+1,x+n+1);sort(y+1,y+n+1);
for(i=1;i<=n/2;i++)
{s+=max(x[n-i+1]-x[i]-a,0);
 s+=max(y[n-i+1]-y[i]-b,0);}
fo<<s;
    return 0;
}