Cycle through the array checking every element

Hi, I'm pretty new to AutoIt (I can only imagine how many times did you read something like that ). 
I'm trying to make a simple script for personal use. What I need from it is to cycle through the arrayed list of processes and kill it if it exists.
This is what I came up to:
 

    Local $Pss[4]
     $Pss[0]="notepad.exe"
     $Pss[1]="qip.exe"
     $Pss[2]="Skype.exe"
     $Pss[3]="Opera.exe"
 
Func KillALl()
     
    For $s = 0 To $s = 4
        if ProcessExists($Pss[$s]) then
            ProcessClose($Pss[$s])
            Sleep(100)
        EndIf
        Next
 
EndFunc

Obviously it doesn't work I can't find anything similiar on the net.