#include <bits/stdc++.h>

using namespace std;
ifstream r("inundatii.in");
ofstream w("inundatii.out");

int n;
long long x[50002], y[50002], z[50002], sol;
int main()
{
    r>>n;
    for(int i=1; i<=n; i++)
    {
        r>>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]);
    }
    w<<sol<<"\n";
    return 0;
}