Introduction - If you have any usage issues, please Google them yourself
Z tour takes us around a matrix recursive manner. Example:
For N = 4
4 5 6 7
3 1 8 15
2 9 16 14
10 11 12 13
For N = 5
7 8 9 10 11
6 1 2 12 22
5 3 13 23 21
4 14 24 25 20
15 16 17 18 19