Олимпиадный тренинг

Задача 42449. Spiral filling


Given a number n. Create an array A[2*n+1][2*n+1] and fill it in a spiral, starting with the number 0 in the center cell  ;A[n+1][n+1]. The spiral goes up, then twists counterclockwise.

Input
The program receives a number as input  n.

Imprint 
The program should output the resulting array, using exactly 3 characters for each number.
 
Examples
# Input Output
1 2
 12 11 10 9 24
 13 2 1 8 23
 14 3 0 7 22
 15 4 5 6 21
 16 17 18 19 20