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D. Cube Snake

time limit per test

2 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputYou've got an *n* × *n* × *n* cube, split into unit cubes. Your task is to number all unit cubes in this cube with positive integers from 1 to *n*^{3} so that:

- each number was used as a cube's number exactly once;
- for each 1 ≤
*i*<*n*^{3}, unit cubes with numbers*i*and*i*+ 1 were neighbouring (that is, shared a side); - for each 1 ≤
*i*<*n*there were at least two different subcubes with sizes*i*×*i*×*i*, made from unit cubes, which are numbered with consecutive numbers. That is, there are such two numbers*x*and*y*, that the unit cubes of the first subcube are numbered by numbers*x*,*x*+ 1, ...,*x*+*i*^{3}- 1, and the unit cubes of the second subcube are numbered by numbers*y*,*y*+ 1, ...,*y*+*i*^{3}- 1.

Find and print the required numeration of unit cubes of the cube.

Input

The first line contains a single integer *n* (1 ≤ *n* ≤ 50) — the size of the cube, whose unit cubes need to be numbered.

Output

Print all layers of the cube as *n* *n* × *n* matrices. Separate them with new lines. Print the layers in the order in which they follow in the cube. See the samples for clarifications.

It is guaranteed that there always is a solution that meets the conditions given in the problem statement.

Examples

Input

3

Output

1 4 17

2 3 18

27 26 19

8 5 16

7 6 15

24 25 20

9 12 13

10 11 14

23 22 21

Note

In the sample the cubes with sizes 2 × 2 × 2 are numbered with integers 1, ..., 8 and 5, ..., 12.

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