Code archives/Algorithms/Pick random element from list or array

' 	--+-----------------------------------------------------------------------------------------+--
'	  |   This code was originally written by Sophie Kirschner (sophiek@pineapplemachine.com)   |  
' 	  | It is released as public domain. Please don't interpret that as liberty to claim credit |  
' 	  |   that isn't yours, or to sell this code when it could otherwise be obtained for free   |  
'	  |                because that would be a really shitty thing of you to do.                |
' 	--+-----------------------------------------------------------------------------------------+--



SuperStrict

Import brl.random
Import brl.linkedlist

Function RandFromArray:Object(array:Object[])
	Assert array
	Return array[Rand(0,array.length-1)]
End Function
Function RandFromList:Object(list:TList)
	Assert list
	Return list.valueatindex(Rand(0,list.count()-1))
End Function
Function RandLinkFromList:TLink(list:TList)
	Assert list
	Local link:TLink=list._head._succ,index%=Rand(0,list.count()-1)
	While link<>list._head
		If index=0 Then Return link
		link=link._succ;index:-1
	Wend
	Return Null
End Function

' Example code

Rem

SeedRnd MilliSecs()

Local testarray$[]=["a","b","c","d","e","f"]
Local testlist:TList=ListFromArray(testarray)
Print String(RandFromArray(testarray))
Print String(RandFromList(testlist))
Print String(RandLinkFromList(testlist)._value)

EndRem