North
West East
South

0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
0

-1
-2

-3

-4
-5

-6
-7

-8
-9

-10
-11
-12

-13
-14
-15

-16
-17
-18
-19
-20
-21
-22
-23
-24
-25
-26
-27
-28
-29
-30