Problem9657--ABC180 —— E - Traveling Salesman among Aerial Cities

9657: ABC180 —— E - Traveling Salesman among Aerial Cities

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Time Limit : 1.000 sec  Memory Limit : 512 MiB

Description

In a three-dimensional space, there are $N$ cities: City $1$ through City $N$. City $i$ is at point $(X_i,Y_i,Z_i)$.

The cost it takes to travel from a city at point $(a,b,c)$ to a city at point $(p,q,r)$ is $|p-a|+|q-b|+\max(0,r-c)$.

Find the minimum total cost it takes to start at City $1$, visit all other cities at least once, and return to City $1$.

Input

Input is given from Standard Input in the following format:

```
$N$
$X_1$ $Y_1$ $Z_1$
$\vdots$
$X_N$ $Y_N$ $Z_N$
```

Output

Print the minimum total cost it takes to start at City $1$, visit all other cities at least once, and return to City $1$.

Constraints

-   $2 \leq N \leq 17$
-   $-10^6 \leq X_i,Y_i,Z_i \leq 10^6$
-   No two cities are at the same point.
-   All values in input are integers.

Sample 1 Input

2
0 0 0
1 2 3

Sample 1 Output

9

The cost it takes to travel from City 1 to City 2 is ∣1−0∣+∣2−0∣+max⁡(0,3−0)=6.

The cost it takes to travel from City 2 to City 1 is ∣0−1∣+∣0−2∣+max⁡(0,0−3)=3.

Thus, the total cost will be 9.

Sample 2 Input

3
0 0 0
1 1 1
-1 -1 -1

Sample 2 Output

10
For example, we can visit the cities in the order 1, 2, 1, 3, 1 to make the total cost 10. Note that we can come back to City 1 on the way.

Sample 3 Input

17
14142 13562 373095
-17320 508075 68877
223606 -79774 9979
-24494 -89742 783178
26457 513110 -64591
-282842 7124 -74619
31622 -77660 -168379
-33166 -24790 -3554
346410 16151 37755
-36055 51275 463989
37416 -573867 73941
-3872 -983346 207417
412310 56256 -17661
-42426 40687 -119285
43588 -989435 -40674
-447213 -59549 -99579
45825 7569 45584

Sample 3 Output

6519344

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