#include <bits/stdc++.h>
using namespace std;
int main() {
  int minx, maxx, miny, maxy;
  minx = miny = 10000009;
  maxx = maxy = -10000009;
  int i, n;
  scanf("%d", &n);
  for (i = 0; i < n; i++) {
    int x, y;
    scanf("%d%d", &x, &y);
    minx = min(x + y, minx);
    miny = min(x - y, miny);
    maxx = max(x + y, maxx);
    maxy = max(x - y, maxy);
  }
  printf("%d\n", maxx - minx + maxy - miny + 4);
}
