#include <bits/stdc++.h>
using namespace std;
int a = -3000000, b = -3000000, c = -3000000, d = -3000000;
int main() {
  int n, x, y;
  cin >> n;
  while (n--) {
    cin >> x >> y;
    a = max(a, x + y);
    b = max(b, x - y);
    c = max(c, y - x);
    d = max(d, -x - y);
  }
  cout << a + b + c + d + 4 << endl;
}
