#include <stdio.h>
#include <stdlib.h>
#include <algorithm>
int lin[50001], col[50001];

int main()
{
  int n, a, b, ans, i, j;
  FILE *fi=fopen("tribute.in", "r"), *fo=fopen("tribute.out", "w");
  fscanf(fi, "%d%d%d", &n, &a, &b);
  for(i=0;i<n;i++)
    fscanf(fi, "%d%d", &lin[i], &col[i]);
  std::sort(lin,lin+n);
  std::sort(col,col+n);
  i=0;
  j=n-1;
  while(i<=j){
    if(lin[j]-lin[i]-a>0)
      ans+=lin[j]-lin[i]-a;
    if(col[j]-col[i]-b>0)
      ans+=col[j]-col[i]-b;
    i++;
    j--;
  }
  fprintf(fo, "%d", ans);
  fclose(fi);
  fclose(fo);
  return 0;
}