0		10		20		30
1-2		11-12		21-22		31-32
2-3		12-13		22-23		32-33
3-4		13-14		23-24		33-34
5		15		25		35
6-7		16-17		26-27		36-37
7-8		17-18		27-28		37-38
8-9		18-19		28-29		38-39

   

40		50		60		70
41-42		51-52		61-62		71-72
42-43		52-53		62-63		72-73
43-44		53-54		63-64		73-74
45		55		65		75
46-47		56-57		66-67		76-77
47-48		57-58		67-68		77-78
48-49		58-59		68-69		78-79