Ascending
|--------------------------------------8-| 
|------------------------------8-10-11---| 
|-------------------------8-10-----------| 
|-----------------8-10-12----------------| 
|---------8-10-12------------------------| 
|-8-10-11--------------------------------| 


               Descending
|--------------------------------------|
|-11-10-8------------------------------|
|---------10-8-------------------------|
|--------------12-10-8-----------------|
|----------------------12-10-8---------|
|------------------------------11-10-8-|