Your task is to construct an $n \times n$ grid where each square has the smallest nonnegative integer that does not appear to the left on the same row or above on the same column.
The only line has an integer $n$ .
Print the grid according to the example.
5\n
0 1 2 3 4 1 0 3 2 5 2 3 0 1 6 3 2 1 0 7 4 5 6 7 0· · · · \n · · · · \n · · · · \n · · · · \n · · · · \n