peek after make    = 100
bump(+5)           = 105
bump(+3)           = 108
peek after bumps   = 108
ctr label          = ctr-a
ctr peek           = 50
ctr after bump     = 57
list[0] peek      = 0
list[1] peek      = 10
list[2] peek      = 20
list[0] after bump= 1
list[1] after bump= 11
list[2] after bump= 21