Given a cube A of size n×n×n. On cell (x,y,z) written an integer Ax,y,z.
From (x,y,z), you can reach (x′,y′,z′) if |x−x′|+|y−y′|+|z−z′|=1.
You are currently standing at (1,1,1). Find the shortest cost to reach (n,n,n) knowing that moving to cell (i,j,k) costs you Ai,j,k.
### Input
- The first line contains an integer n.
- The next n×n lines, the ith line contains n integers A_{\lfloor \frac{i - 1}{n} + 1 \rfloor, (i - 1) \mod n + 1, k}. In other words, the first group of n lines is the matrix A_{1, j, k}, the second group of n lines is the matrix A_{2, j, k} and so on...
### Output
- Print the weight of the shortest path from (1, 1, 1) to (n, n, n).
### Constraints
- 1 \le n \le 100.
- 1 \le A_{i, j, k} \le 1000.
### Example
Input:
2
1 2
3 1
3 3
1 2
Output:
5
#### Note:
- Moving from (1, 1, 1) to (1, 1, 2) cost 2.
- Moving from (1, 1, 2) to (1, 2, 2) cost 1.
- Moving from (1, 2, 2) to (2, 2, 2) cost 2.