#include <fstream>
#include <algorithm>
#define int long long
using namespace std;
/// inund

const int nmax = 1e5;
struct input {
  int x, y, z;
}v[nmax + 1];

signed main(){

  ifstream fin ("inundatii.in");
  ofstream fout ("inundatii.out");

  int n;
  fin >> n;

  for (int i = 1; i <= n; i++){
    fin >> v[i].x >> v[i].y >> v[i].z;
    v[i].x -= i;
    v[i].y -= i;
    v[i].z -= i;
  }
  int sol = 0;
  for (int i = 1; i <= n; i++){
    sol += abs (v[i].x - v[n / 2 + 1].x) + abs (v[i].y - v[n / 2 + 1].y) + abs (v[i].z - v[n / 2 + 1].z);
  }

  fout << sol;
  return 0;
}