#include <bits/stdc++.h>
using namespace std;
int main(void) {
  int n, a = -0x3f3f3f3f, b = -0x3f3f3f3f, c = 0x3f3f3f3f, d = 0x3f3f3f3f;
  scanf("%d", &n);
  for (int i = 1, x, y; i <= n; i++) {
    scanf("%d%d", &x, &y);
    a = max(x + y, a);
    b = max(x - y, b);
    c = min(x + y, c);
    d = min(x - y, d);
  }
  printf("%d\n", a + b - c - d + 4);
  return 0;
}
