On Fri, Nov 9, 2018 at 1:26 PM Roelof Wobben <[email protected]> wrote:
> Thanks all.
>
> This code seems to do the job
>
> santaFloorOnBasement
> "calculates which step take Santa to the basement"
> | index|
> index := 1.
> [floor ~= -1 ] whileTrue:
> [ floor := ((input at: index) = '(' )
> ifTrue: [ floor + 1 ]
> ifFalse: [ floor - 1 ].
> index := index + 1 ].
>
> ^ index -1
>
You can also think of it from the perspective of data processing and not
instruction coding (and mangling of indexes).
stepChanges := input collect: [ :c |
floor := floor + (c = '(' ifTrue: [ 1 ] ifFalse: [ -1 ]).
floor
].
stepChanges detectIndex: [ :each | each = -1 ] ifNone: [ 'invalid input yo'
].
Peter
