RosettaCodeData/Task/Permutations/AutoHotkey/permutations-2.ahk

34 lines
1.0 KiB
AutoHotkey

P(n,k="",opt=0,delim="",str="") { ; generate all n choose k permutations lexicographically
;1..n = range, or delimited list, or string to parse
; to process with a different min index, pass a delimited list, e.g. "0`n1`n2"
;k = length of result
;opt 0 = no repetitions
;opt 1 = with repetitions
;opt 2 = run for 1..k
;opt 3 = run for 1..k with repetitions
;str = string to prepend (used internally)
;returns delimited string, error message, or (if k > n) a blank string
i:=0
If !InStr(n,"`n")
If n in 2,3,4,5,6,7,8,9
Loop, %n%
n := A_Index = 1 ? A_Index : n "`n" A_Index
Else
Loop, Parse, n, %delim%
n := A_Index = 1 ? A_LoopField : n "`n" A_LoopField
If (k = "")
RegExReplace(n,"`n","",k), k++
If k is not Digit
Return "k must be a digit."
If opt not in 0,1,2,3
Return "opt invalid."
If k = 0
Return str
Else
Loop, Parse, n, `n
If (!InStr(str,A_LoopField) || opt & 1)
s .= (!i++ ? (opt & 2 ? str "`n" : "") : "`n" )
. P(n,k-1,opt,delim,str . A_LoopField . delim)
Return s
}