#include <fstream>
#include <algorithm>

using namespace std;

ifstream cin ("tribute.in");
ofstream cout ("tribute.out");
int v1[50001],v2[50001];
int main() {
  int n,a,b,i,s;
  cin>>n>>a>>b;
  for(i=1;i<=n;i++)
    cin>>v1[i]>>v2[i];
  sort(v1+1,v1+n+1);
  sort(v2+1,v2+n+1);
  s=0;
  for(i=1;i<=n;i++){
    if(v1[i+1]-v1[n-i]-a>0)
      s+=v1[i+1]-v1[n-i]-a;
    if(v2[i+1]-v2[n-i]-b>0)
      s+=v2[i+1]-v2[n-i]-b;
  }
  cout<<s;
  return 0;
}