#include <bits/stdc++.h>
int main() {
  int n, max1 = -2000020, max2 = -2000020, min1 = 2000020, min2 = 2000020;
  scanf(" %d", &n);
  int i, x, y;
  for (i = 0; i < n; i++) {
    scanf(" %d %d", &x, &y);
    if (x + y > max1) max1 = x + y;
    if (x - y > max2) max2 = x - y;
    if (x + y < min1) min1 = x + y;
    if (x - y < min2) min2 = x - y;
  }
  printf("%d", max1 + max2 - min1 - min2 + 4);
  return 0;
}
