Problem C

Statement
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Description:
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 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 $$$n \times n$$$.

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

Output Format:
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.

Note:
In the first example, XOR of each row and each column is $$$13$$$.

In the second example, XOR of each row and each column is $$$60$$$.