A12801 | Magic Grid

Let us define a magic grid to be a square matrix of integers of size $n \times n$ , satisfying the following conditions.

- All integers from $0$ to $(n^2 - 1)$ inclusive appear in the matrix exactly once.
- [Bitwise XOR](https://en.wikipedia.org/wiki/Bitwise_operation#XOR) of all elements in a row or a column must be the same for each row and column.

You are given an integer $n$ which is a multiple of $4$ . Construct a magic grid of size $n \times n$ .

The only line of input contains an integer $n$ ( $4 \leq n \leq 1000$ ). It is guaranteed that $n$ is a multiple of $4$ .

Print a magic grid, i.e. $n$ lines, the $i$ -th of which contains $n$ space-separated integers, representing the $i$ -th row of the grid.

If there are multiple answers, print any. We can show that an answer always exists.