#include <bits/stdc++.h>
using namespace std;
int main() {
  int i, j, n;
  int a, b;
  cin >> n;
  int minx = 0x3fffffff;
  int miny = 0x3fffffff;
  int maxx = -0x3fffffff;
  int maxy = -0x3fffffff;
  for (i = 0; i < n; i++) {
    cin >> a >> b;
    minx = min(minx, a - b);
    maxx = max(maxx, a - b);
    miny = min(miny, a + b);
    maxy = max(maxy, a + b);
  }
  cout << (maxx - minx) + (maxy - miny) + 4 << endl;
}
