#include <bits/stdc++.h>
using namespace std;
ifstream fin("inundatii.in");
ofstream fout("inundatii.out");
#define int long long
int x[50002], y[50002], z[50002], mx, my, mz, sol;
int32_t main(){
    int n;fin>>n;
    for(int i=1;i<=n;++i) fin>>x[i]>>y[i]>>z[i];x[i]-=i;y[i]-=i;z[i]-=i;
    for(int i=1;i<=n;++i) sol+=abs(x[i]-x[n/2+1])+abs(y[i]-y[n/2+1])+abs(z[i]-z[n/2+1]);
    fout<<sol<<"\n";
    return 0;
}