#include <cstdio>

using namespace std;

typedef long long ll;
const int N = 50000 + 7;
int n;
int a[N], b[N], c[N];

int abs(int x) {
        if (x < 0)
                return -x;
        else
                return x;
}

int main() {
        freopen ("inundatii.in", "r", stdin);
        freopen ("inundatii.out", "w", stdout);

        scanf("%d", &n);
        for (int i = 1; i <= n; i++) {
                scanf("%d %d %d", &a[i], &b[i], &c[i]);
                a[i] -= i;
                b[i] -= i;
                c[i] -= i;
        }

        ll ans = 0;
        int half = (n + 1) / 2;
        for (int i = 1; i <= n; i++) {
                ans += abs(a[i] - a[half]);
                ans += abs(b[i] - b[half]);
                ans += abs(c[i] - c[half]);
        }
        printf("%lld\n", ans);

        return 0;
}