Having Trouble moving circle up and down continuously

[zunaed]

I'm trying to figure out how to make a circle move up and down, so far i have

var inky:=135

loop
if inky>35 then
inky:=inky-1
elsif inky<35 then
inky:=inky+1
end if
Draw.FillOval (335, inky, 10, 10, brightcyan)
Draw.FillBox (325, 135, 345, 125, brightcyan)
end loop

I knew how to do this two years ago but haven't used it since and now I cant seem to remember the logic behind how it works. Can someone plz help

[gitoxa]

I'd use a variable for whether or not the circle is currently moving up or down. (hint: 2 choices)

[zunaed]

YES! Just figured it out thanks for the help.