#include <bits/stdc++.h>
using namespace std;
const long long Inf = 10000000000000LL;
int main() {
  long long l, u, r, d;
  int n, x, y;
  l = d = Inf;
  u = r = -Inf;
  scanf("%d", &n);
  while (n--) {
    scanf("%d %d", &x, &y);
    d = min(d, (long long)x + y);
    u = max(u, (long long)x + y);
    l = min(l, (long long)x - y);
    r = max(r, (long long)x - y);
  }
  printf("%I64d\n", u - d + r - l + 4LL);
  return 0;
}
