#include <stdio.h>
#define NMAX 50050

int x[NMAX], y[NMAX], z[NMAX], n, s, i, v1, v2, v3;

int main()
{
        freopen("inundatii.in", "r", stdin);
        scanf("%d", &n);
        for (i = 1; i <= n; i++) scanf("%d%d%d", x+i, y+i, z+i), x[i]-=i, y[i]-=i, z[i]-=i;
        v1 = x[n/2]; v2 = y[n/2]; v3 = z[n/2];
        for (s = 0, i = 1; i <= n; i++) s = s+abs(x[i]-v1)+abs(y[i]-v2)+abs(z[i]-v3);
        freopen("inundatii.out", "w", stdout);
        printf("%d\n", s);
        return 0;
}