# Factorial base numbers indexing permutations of a collection

Factorial base numbers indexing permutations of a collection
You are encouraged to solve this task according to the task description, using any language you may know.

You need a random arrangement of a deck of cards, you are sick of lame ways of doing this. This task is a super-cool way of doing this using factorial base numbers. The first 25 factorial base numbers in increasing order are: 0.0.0, 0.0.1, 0.1.0, 0.1.1, 0.2.0, 0.2.1, 1.0.0, 1.0.1, 1.1.0, 1.1.1,1.2.0, 1.2.1, 2.0.0, 2.0.1, 2.1.0, 2.1.1, 2.2.0, 2.2.1, 3.0.0, 3.0.1, 3.1.0, 3.1.1, 3.2.0, 3.2.1, 1.0.0.0 Observe that the least significant digit is base 2 the next base 3, in general an n-digit factorial base number has digits n..1 in base n+1..2.

I want to produce a 1 to 1 mapping between these numbers and permutations:-

```       0.0.0 -> 0123
0.0.1 -> 0132
0.1.0 -> 0213
0.1.1 -> 0231
0.2.0 -> 0312
0.2.1 -> 0321
1.0.0 -> 1023
1.0.1 -> 1032
1.1.0 -> 1203
1.1.1 -> 1230
1.2.0 -> 1302
1.2.1 -> 1320
2.0.0 -> 2013
2.0.1 -> 2031
2.1.0 -> 2103
2.1.1 -> 2130
2.2.0 -> 2301
2.2.1 -> 2310
3.0.0 -> 3012
3.0.1 -> 3021
3.1.0 -> 3102
3.1.1 -> 3120
3.2.0 -> 3201
3.2.1 -> 3210
```

The following psudo-code will do this: Starting with m=0 and Ω, an array of elements to be permutated, for each digit g starting with the most significant digit in the factorial base number.

If g is greater than zero, rotate the elements from m to m+g in Ω (see example) Increment m and repeat the first step using the next most significant digit until the factorial base number is exhausted. For example: using the factorial base number 2.0.1 and Ω = 0 1 2 3 where place 0 in both is the most significant (left-most) digit/element.

Step 1: m=0 g=2; Rotate places 0 through 2. 0 1 2 3 becomes 2 0 1 3 Step 2: m=1 g=0; No action. Step 3: m=2 g=1; Rotate places 2 through 3. 2 0 1 3 becomes 2 0 3 1

Let me work 2.0.1 and 0123

```    step 1 n=0 g=2 Ω=2013
step 2 n=1 g=0 so no action
step 3 n=2 g=1 Ω=2031
```

``` First use your function to recreate the above table.
Secondly use your function to generate all permutaions of 11 digits, perhaps count them don't display them, compare this method with
Thirdly here following are two ramdom 51 digit factorial base numbers I prepared earlier:
39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0
51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1
use your function to crate the corresponding permutation of the following shoe of cards:
A♠K♠Q♠J♠10♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥10♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦10♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣10♣9♣8♣7♣6♣5♣4♣3♣2♣
Finally create your own 51 digit factorial base number and produce the corresponding permutation of the above shoe
```

## F#

The Functıons
` // Factorial base numbers indexing permutations of a collection// Nigel Galloway: December 7th., 2018let lN2p (c:int[]) (Ω:'Ω[])=  let Ω=Array.copy Ω  let rec fN i g e l=match l-i with 0->Ω.[i]<-e |_->Ω.[l]<-Ω.[l-1]; fN i g e (l-1)// rotate right  [0..((Array.length Ω)-2)]|>List.iter(fun n->let i=c.[n] in if i>0 then fN n (i+n) Ω.[i+n] (i+n)); Ωlet lN n =  let    Ω=(Array.length n)  let fN g=if n.[g]=Ω-g then n.[g]<-0; false else n.[g]<-n.[g]+1; true  seq{yield n; while [1..Ω]|>List.exists(fun g->fN (Ω-g)) do yield n}`
Re-create the table
` lN [|0;0;0|] |> Seq.iter (fun n->printfn "%A -> %A" n (lN2p n [|0;1;2;3|]));; `
Output:
```[|0; 0; 0|] -> [|0; 1; 2; 3|]
[|0; 0; 1|] -> [|0; 1; 3; 2|]
[|0; 1; 0|] -> [|0; 2; 1; 3|]
[|0; 1; 1|] -> [|0; 2; 3; 1|]
[|0; 2; 0|] -> [|0; 3; 1; 2|]
[|0; 2; 1|] -> [|0; 3; 2; 1|]
[|1; 0; 0|] -> [|1; 0; 2; 3|]
[|1; 0; 1|] -> [|1; 0; 3; 2|]
[|1; 1; 0|] -> [|1; 2; 0; 3|]
[|1; 1; 1|] -> [|1; 2; 3; 0|]
[|1; 2; 0|] -> [|1; 3; 0; 2|]
[|1; 2; 1|] -> [|1; 3; 2; 0|]
[|2; 0; 0|] -> [|2; 0; 1; 3|]
[|2; 0; 1|] -> [|2; 0; 3; 1|]
[|2; 1; 0|] -> [|2; 1; 0; 3|]
[|2; 1; 1|] -> [|2; 1; 3; 0|]
[|2; 2; 0|] -> [|2; 3; 0; 1|]
[|2; 2; 1|] -> [|2; 3; 1; 0|]
[|3; 0; 0|] -> [|3; 0; 1; 2|]
[|3; 0; 1|] -> [|3; 0; 2; 1|]
[|3; 1; 0|] -> [|3; 1; 0; 2|]
[|3; 1; 1|] -> [|3; 1; 2; 0|]
[|3; 2; 0|] -> [|3; 2; 0; 1|]
[|3; 2; 1|] -> [|3; 2; 1; 0|]
```
Shuffles
` let shoe==[|"A♠";"K♠";"Q♠";"J♠";"10♠";"9♠";"8♠";"7♠";"6♠";"5♠";"4♠";"3♠";"2♠";"A♥";"K♥";"Q♥";"J♥";"10♥";"9♥";"8♥";"7♥";"6♥";"5♥";"4♥";"3♥";"2♥";"A♦";"K♦";"Q♦";"J♦";"10♦";"9♦";"8♦";"7♦";"6♦";"5♦";"4♦";"3♦";"2♦";"A♣";"K♣";"Q♣";"J♣";"10♣";"9♣";"8♣";"7♣";"6♣";"5♣";"4♣";"3♣";"2♣";|]//Random Shufflelet N=System.Random() in lc2p [|for n in 52..-1..2 do yield N.Next(n)|] shoe|>Array.iter (printf "%s ");printfn ""//Task ShuffleslN2p [|39;49;7;47;29;30;2;12;10;3;29;37;33;17;12;31;29;34;17;25;2;4;25;4;1;14;20;6;21;18;1;1;1;4;0;5;15;12;4;3;10;10;9;1;6;5;5;3;0;0;0|] shoe|>Array.iter (printf "%s ");printfn ""lN2p [|51;48;16;22;3;0;19;34;29;1;36;30;12;32;12;29;30;26;14;21;8;12;1;3;10;4;7;17;6;21;8;12;15;15;13;15;7;3;12;11;9;5;5;6;6;3;4;0;3;2;1|] shoe|>Array.iter (printf "%s ");printfn "" `
Output:
```J♣ Q♦ 10♣ 10♠ 3♥ 7♠ 8♥ 7♥ 8♦ 10♦ 4♥ 9♥ 8♠ K♥ 4♣ 5♥ K♣ Q♥ 9♠ A♦ Q♠ 6♦ K♦ K♠ 2♣ 6♠ 7♦ J♦ 2♥ 5♠ 4♦ 3♦ 6♣ J♥ 9♦ 4♠ 3♣ 2♠ 3♠ 10♥ Q♣ A♥ 2♦ A♠ 7♣ A♣ 9♣ 6♥ 5♦ 5♣ J♠ 8♣

A♣ 3♣ 7♠ 4♣ 10♦ 8♦ Q♠ K♥ 2♠ 10♠ 4♦ 7♣ J♣ 5♥ 10♥ 10♣ K♣ 2♣ 3♥ 5♦ J♠ 6♠ Q♣ 5♠ K♠ A♦ 3♦ Q♥ 8♣ 6♦ 9♠ 8♠ 4♠ 9♥ A♠ 6♥ 5♣ 2♦ 7♥ 8♥ 9♣ 6♣ 7♦ A♥ J♦ Q♦ 9♦ 2♥ 3♠ J♥ 4♥ K♦

2♣ 5♣ J♥ 4♥ J♠ A♠ 5♥ A♣ 6♦ Q♠ 9♣ 3♦ Q♥ J♣ 10♥ K♣ 10♣ 5♦ 7♥ 10♦ 3♠ 8♥ 10♠ 7♠ 6♥ 5♠ K♥ 4♦ A♥ 4♣ 2♥ 9♦ Q♣ 8♣ 7♦ 6♣ 3♥ 6♠ 7♣ 2♦ J♦ 9♥ A♦ Q♦ 8♦ 4♠ K♦ K♠ 3♣ 2♠ 8♠ 9♠```
Comparıson wıth [Permutations(F#)]
` let g=[|0..10|]lC 10 |> Seq.map(fun n->lc2p n g) |>  Seq.length `
Output:
```Real: 00:01:08.430, CPU: 00:01:08.970, GC gen0: 9086, gen1: 0
val it : int = 39916800
```

8GB of memory is insufficient for rc's perm task

## Factor

`USING: assocs io kernel literals math math.factorialsmath.parser math.ranges prettyprint qw random sequencessplitting ;RENAME: factoradic math.combinatorics.private => _factoradicRENAME: rotate sequences.extras => _rotateIN: rosetta-code.factorial-permutations CONSTANT: shoe \$[    qw{ A K Q J 10 9 8 7 6 5 4 3 2 } qw{ ♠ ♥ ♦ ♣ }    [ append ] cartesian-map flip concat] ! Factor can already make factoradic numbers, but they always! have a least-significant digit of 0 to remove.: factoradic ( n -- seq )    _factoradic dup [ drop but-last ] unless-empty ; ! Convert "3.1.2.0" to { 3 1 2 0 }, for example.: string>factoradic ( str -- seq )    "." split [ string>number ] map ; ! Rotate a subsequence.! E.g. 0 2 { 3 1 2 0 } (rotate) -> { 2 3 1 0 }.: (rotate) ( from to seq -- newseq )    [ 1 + ] dip [ snip ] [ subseq ] 3bi -1 _rotate glue ; ! Only rotate a subsequence if from does not equal to.: rotate ( from to seq -- newseq )    2over = [ 2nip ] [ (rotate) ] if ; ! The pseudocode from the task description: fpermute ( factoradic -- permutation )    dup length 1 + <iota> swap <enumerated>    [ over + rot rotate ] assoc-each ; ! Use a factoradic number to index permutations of a collection.: findex ( factoradic seq -- permutation )    [ fpermute ] [ nths concat ] bi* ; : .f ( seq -- ) [ "." write ] [ pprint ] interleave ;   ! Print a factoradic number: .p ( seq -- ) [ pprint ] each nl ;                    ! Print a permutation : show-table ( -- )    "Generate table" print 24    [ factoradic 3 0 pad-head dup .f fpermute " -> " write .p ]    each-integer nl ; : show-shuffles ( -- )    "Generate given task shuffles" print    "Original deck:" print shoe concat print nl    "39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0"    "51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1"    [ [ print ] [ string>factoradic shoe findex print nl ] bi ] [email protected] ; : show-random-shuffle ( -- )    "Random shuffle:" print    51 52 [ n! ] [email protected] [a,b] random factoradic shoe findex print ; : main ( -- ) show-table show-shuffles show-random-shuffle ; MAIN: main`
Output:
```Generate table
0.0.0 -> 0123
0.0.1 -> 0132
0.1.0 -> 0213
0.1.1 -> 0231
0.2.0 -> 0312
0.2.1 -> 0321
1.0.0 -> 1023
1.0.1 -> 1032
1.1.0 -> 1203
1.1.1 -> 1230
1.2.0 -> 1302
1.2.1 -> 1320
2.0.0 -> 2013
2.0.1 -> 2031
2.1.0 -> 2103
2.1.1 -> 2130
2.2.0 -> 2301
2.2.1 -> 2310
3.0.0 -> 3012
3.0.1 -> 3021
3.1.0 -> 3102
3.1.1 -> 3120
3.2.0 -> 3201
3.2.1 -> 3210

Original deck:
A♠K♠Q♠J♠10♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥10♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦10♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣10♣9♣8♣7♣6♣5♣4♣3♣2♣

39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0
A♣3♣7♠4♣10♦8♦Q♠K♥2♠10♠4♦7♣J♣5♥10♥10♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦

51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1
2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣10♥K♣10♣5♦7♥10♦3♠8♥10♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠

Random shuffle:
5♠K♣K♠4♣8♥7♠Q♥J♦3♠A♦3♣8♣6♥A♥3♥A♣10♥9♠10♣5♣J♣J♠J♥2♣K♥Q♦Q♣7♣6♦7♥2♥5♥2♠10♦2♦A♠4♦8♠4♠7♦10♠6♣9♣5♦4♥8♦9♦3♦6♠K♦9♥Q♠
```

## Go

`package main import (    "fmt"    "math/rand"    "strconv"    "strings"    "time") func factorial(n int) int {    fact := 1    for i := 2; i <= n; i++ {        fact *= i    }    return fact} func genFactBaseNums(size int, countOnly bool) ([][]int, int) {    var results [][]int    count := 0    for n := 0; ; n++ {        radix := 2        var res []int = nil        if !countOnly {             res = make([]int, size)        }        k := n        for k > 0 {            div := k / radix            rem := k % radix            if !countOnly {                if radix <= size+1 {                    res[size-radix+1] = rem                }            }            k = div            radix++        }        if radix > size+2 {            break        }        count++        if !countOnly {            results = append(results, res)        }    }    return results, count} func mapToPerms(factNums [][]int) [][]int {    var perms [][]int    psize := len(factNums[0]) + 1    start := make([]int, psize)    for i := 0; i < psize; i++ {        start[i] = i    }    for _, fn := range factNums {        perm := make([]int, psize)        copy(perm, start)        for m := 0; m < len(fn); m++ {            g := fn[m]            if g == 0 {                continue            }            first := m            last := m + g            for i := 1; i <= g; i++ {                temp := perm[first]                for j := first + 1; j <= last; j++ {                    perm[j-1] = perm[j]                }                perm[last] = temp            }        }        perms = append(perms, perm)    }    return perms} func join(is []int, sep string) string {    ss := make([]string, len(is))    for i := 0; i < len(is); i++ {        ss[i] = strconv.Itoa(is[i])    }    return strings.Join(ss, sep)} func undot(s string) []int {    ss := strings.Split(s, ".")    is := make([]int, len(ss))    for i := 0; i < len(ss); i++ {        is[i], _ = strconv.Atoi(ss[i])    }    return is} func main() {    rand.Seed(time.Now().UnixNano())     // Recreate the table.    factNums, _ := genFactBaseNums(3, false)    perms := mapToPerms(factNums)    for i, fn := range factNums {        fmt.Printf("%v -> %v\n", join(fn, "."), join(perms[i], ""))    }     // Check that the number of perms generated is equal to 11! (this takes a while).    _, count := genFactBaseNums(10, true)    fmt.Println("\nPermutations generated =", count)    fmt.Println("compared to 11! which  =", factorial(11))    fmt.Println()     // Generate shuffles for the 2 given 51 digit factorial base numbers.    fbn51s := []string{        "39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0",        "51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1",    }    factNums = [][]int{undot(fbn51s[0]), undot(fbn51s[1])}    perms = mapToPerms(factNums)    shoe := []rune("A♠K♠Q♠J♠T♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥T♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦T♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣T♣9♣8♣7♣6♣5♣4♣3♣2♣")    cards := make([]string, 52)    for i := 0; i < 52; i++ {        cards[i] = string(shoe[2*i : 2*i+2])        if cards[i][0] == 'T' {            cards[i] = "10" + cards[i][1:]        }    }    for i, fbn51 := range fbn51s {        fmt.Println(fbn51)        for _, d := range perms[i] {            fmt.Print(cards[d])        }        fmt.Println("\n")    }     // Create a random 51 digit factorial base number and produce a shuffle from that.    fbn51 := make([]int, 51)    for i := 0; i < 51; i++ {        fbn51[i] = rand.Intn(52 - i)    }    fmt.Println(join(fbn51, "."))    perms = mapToPerms([][]int{fbn51})    for _, d := range perms[0] {        fmt.Print(cards[d])    }    fmt.Println()}`
Output:

Random for Part 4:

```0.0.0 -> 0123
0.0.1 -> 0132
0.1.0 -> 0213
0.1.1 -> 0231
0.2.0 -> 0312
0.2.1 -> 0321
1.0.0 -> 1023
1.0.1 -> 1032
1.1.0 -> 1203
1.1.1 -> 1230
1.2.0 -> 1302
1.2.1 -> 1320
2.0.0 -> 2013
2.0.1 -> 2031
2.1.0 -> 2103
2.1.1 -> 2130
2.2.0 -> 2301
2.2.1 -> 2310
3.0.0 -> 3012
3.0.1 -> 3021
3.1.0 -> 3102
3.1.1 -> 3120
3.2.0 -> 3201
3.2.1 -> 3210

Permutations generated = 39916800
compared to 11! which  = 39916800

39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0
A♣3♣7♠4♣10♦8♦Q♠K♥2♠10♠4♦7♣J♣5♥10♥10♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦

51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1
2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣10♥K♣10♣5♦7♥10♦3♠8♥10♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠

18.14.25.48.18.9.1.16.15.11.41.8.26.19.36.11.8.21.20.15.15.14.27.10.5.24.0.11.18.12.6.8.5.14.16.10.13.13.9.7.11.1.1.7.0.2.5.0.3.0.0
9♥K♥K♦2♣7♥5♠K♠6♥8♥A♥3♣4♠4♦J♦5♣J♥3♠6♦7♦A♦Q♦2♥7♣10♥8♠8♣A♠10♦Q♣8♦2♠4♥6♠J♣6♣3♦10♣9♣5♦3♥4♣J♠10♠A♣Q♠Q♥K♣9♠2♦7♠5♥9♦
```

## J

Generalized base and antibase, and anagrams are j verbs making this project directly solvable.

```   NB. A is a numerical matrix corresponding to the input and output
A =: _&".;._2[0 :0
0 0 0 0123
0 0 1 0132
0 1 0 0213
0 1 1 0231
0 2 0 0312
0 2 1 0321
1 0 0 1023
1 0 1 1032
1 1 0 1203
1 1 1 1230
1 2 0 1302
1 2 1 1320
2 0 0 2013
2 0 1 2031
2 1 0 2103
2 1 1 2130
2 2 0 2301
2 2 1 2310
3 0 0 3012
3 0 1 3021
3 1 0 3102
3 1 1 3120
3 2 0 3201
3 2 1 3210
)

NB. generalized antibase converts the factorial base representation to integers
4 3 2 #. _ 3 {. A
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

EXPECT =: 10 10 10 10#:{:"1 A

NB. the 0 through 23 anagrams of 0 1 2 3 matches our expactation
EXPECT -: (4 3 2 #. _ 3 {. A) A. 0 1 2 3
1

NB. 6 take EXPECT, for you to see what's been matched
6{.EXPECT
0 1 2 3
0 1 3 2
0 2 1 3
0 2 3 1
0 3 1 2
0 3 2 1

```

## Julia

`function makefactorialbased(N, makelist)    listlist = Vector{Vector{Int}}()    count = 0    while true        divisor = 2        makelist && (lis = zeros(Int, N))        k = count        while k > 0            k, r = divrem(k, divisor)            makelist && (divisor <= N + 1) && (lis[N - divisor + 2] = r)            divisor += 1        end        if divisor > N + 2            break        end        count += 1        makelist && push!(listlist, lis)    end    return count, listlistend function facmap(factnumbase)    perm = [i for i in 0:length(factnumbase)]    for (n, g) in enumerate(factnumbase)        if g != 0            perm[n:n + g] .= circshift(perm[n:n + g], 1)        end    end    permend function factbasenums()    fcount, factnums = makefactorialbased(3, true)    perms = map(facmap, factnums)    for (i, fn) = enumerate(factnums)        println("\$(join(string.(fn), ".")) -> \$(join(string(perms[i]), ""))")    end     fcount, _ = makefactorialbased(10, false)    println("\nPermutations generated = \$fcount, and 11! = \$(factorial(11))\n")     taskrandom = ["39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0",        "51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1"]    perms = map(s -> facmap([parse(Int, s) for s in split(s, ".")]), taskrandom)     cardshoe = split("A♠K♠Q♠J♠T♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥T♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦T♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣T♣9♣8♣7♣6♣5♣4♣3♣2♣", "")    cards = [cardshoe[2*i+1] * cardshoe[2*i+2] for i in 0:51]    printcardshuffle(t, c, o) = (println(t); for i in 1:length(o) print(c[o[i] + 1]) end; println())     println("\nTask shuffles:")    map(i -> printcardshuffle(taskrandom[i], cards, perms[i]), 1:2)     myran = [rand(collect(0:i)) for i in 51:-1:1]    perm = facmap(myran)    println("\nMy random shuffle:")    printcardshuffle(join(string.(myran), "."), cards, perm)end factbasenums() `
Output:
```
0.0.0 -> [0, 1, 2, 3]
0.0.1 -> [0, 1, 3, 2]
0.1.0 -> [0, 2, 1, 3]
0.1.1 -> [0, 2, 3, 1]
0.2.0 -> [0, 3, 1, 2]
0.2.1 -> [0, 3, 2, 1]
1.0.0 -> [1, 0, 2, 3]
1.0.1 -> [1, 0, 3, 2]
1.1.0 -> [1, 2, 0, 3]
1.1.1 -> [1, 2, 3, 0]
1.2.0 -> [1, 3, 0, 2]
1.2.1 -> [1, 3, 2, 0]
2.0.0 -> [2, 0, 1, 3]
2.0.1 -> [2, 0, 3, 1]
2.1.0 -> [2, 1, 0, 3]
2.1.1 -> [2, 1, 3, 0]
2.2.0 -> [2, 3, 0, 1]
2.2.1 -> [2, 3, 1, 0]
3.0.0 -> [3, 0, 1, 2]
3.0.1 -> [3, 0, 2, 1]
3.1.0 -> [3, 1, 0, 2]
3.1.1 -> [3, 1, 2, 0]
3.2.0 -> [3, 2, 0, 1]
3.2.1 -> [3, 2, 1, 0]

Permutations generated = 39916800, and 11! = 39916800

39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0
A♣3♣7♠4♣T♦8♦Q♠K♥2♠T♠4♦7♣J♣5♥T♥T♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦
51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1
2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣T♥K♣T♣5♦7♥T♦3♠8♥T♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠

My random shuffle:
29.18.33.22.0.5.10.1.12.18.3.7.39.7.5.12.8.16.28.4.19.18.19.12.4.15.22.3.13.0.5.16.2.16.0.5.10.11.7.0.2.8.9.4.1.6.0.4.1.0.0
J♦9♥5♦4♥A♠8♠2♠Q♠J♥2♥9♠3♠2♣A♥5♠5♥T♥9♦8♣6♠3♦4♦A♣K♦4♠6♦6♣7♠7♦K♠7♥9♣K♥5♣J♠A♦Q♣T♣8♦T♠6♥7♣3♣T♦8♥4♣Q♥J♣Q♦3♥2♦K♣

```

## Perl

Translation of: Perl 6
`use strict;use warnings;use feature 'say'; sub fpermute {    my(\$f,@a) = @_;    my @f = split /\./, \$f;    for (0..\$#f) {        my @b = @a[\$_ ..  \$_+\$f[\$_]];        unshift @b, splice @b, \$#b, 1; # rotate(-1)        @a[\$_ .. \$_+\$f[\$_]] = @b;    }    join '', @a;} sub base {    my(\$n) = @_;    my @digits;    push(@digits, int \$n/\$_) and \$n = \$n % \$_ for <6 2 1>; # reverse <1! 2! 3!>    join '.', @digits;} say 'Generate table'; for (0..23) {    my \$x = base(\$_);    say \$x . ' -> ' . fpermute(\$x, <0 1 2 3>)} say "\nGenerate the given task shuffles";my @omega = qw<A♠ K♠ Q♠ J♠ 10♠ 9♠ 8♠ 7♠ 6♠ 5♠ 4♠ 3♠ 2♠ A♥ K♥ Q♥ J♥ 10♥ 9♥ 8♥ 7♥ 6♥ 5♥ 4♥ 3♥ 2♥ A♦ K♦ Q♦ J♦ 10♦ 9♦ 8♦ 7♦ 6♦ 5♦ 4♦ 3♦ 2♦ A♣ K♣ Q♣ J♣ 10♣ 9♣ 8♣ 7♣ 6♣ 5♣ 4♣ 3♣ 2♣>; my @books = ('39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0','51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1'); say "Original deck:";say join '', @omega; say "\n\$_\n" . fpermute(\$_,@omega) for @books; say "\nGenerate a random shuffle";say my \$shoe = join '.', map { int rand(\$_) } reverse 0..\$#omega;say fpermute(\$shoe,@omega);`
Output:
```Generate table
0.0.0 -> 0123
0.0.1 -> 0132
0.1.0 -> 0213
0.1.1 -> 0231
0.2.0 -> 0312
0.2.1 -> 0321
1.0.0 -> 1023
1.0.1 -> 1032
1.1.0 -> 1203
1.1.1 -> 1230
1.2.0 -> 1302
1.2.1 -> 1320
2.0.0 -> 2013
2.0.1 -> 2031
2.1.0 -> 2103
2.1.1 -> 2130
2.2.0 -> 2301
2.2.1 -> 2310
3.0.0 -> 3012
3.0.1 -> 3021
3.1.0 -> 3102
3.1.1 -> 3120
3.2.0 -> 3201
3.2.1 -> 3210

Original deck:
A♠K♠Q♠J♠10♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥10♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦10♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣10♣9♣8♣7♣6♣5♣4♣3♣2♣

39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0
A♣3♣7♠4♣10♦8♦Q♠K♥2♠10♠4♦7♣J♣5♥10♥10♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦

51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1
2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣10♥K♣10♣5♦7♥10♦3♠8♥10♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠

Generate a random shuffle
47.33.30.9.2.13.9.43.23.40.11.15.15.1.2.11.23.5.21.30.30.14.27.26.7.20.24.13.10.21.1.10.9.2.10.0.12.11.11.11.10.8.2.0.3.4.4.2.0.1.0.0
6♣7♦10♦5♠Q♠Q♥3♠3♣K♦5♣K♥7♥6♥K♠10♠9♥4♦6♠5♦7♣4♣2♥9♣10♣A♥2♦8♣A♦5♥J♣J♠3♥4♥8♠9♦A♠A♣3♦K♣Q♣6♦J♦4♠9♠10♥Q♦8♦J♥7♠8♥2♠2♣```

## Perl 6

Works with: Rakudo version 2018.11

Using my interpretation of the task instructions as shown on the discussion page.

`sub postfix:<!> (Int \$n) { (flat 1, [\*] 1..*)[\$n] } multi base (Int \$n is copy, 'F', \$length? is copy) {    constant @fact = [\*] 1 .. *;    my \$i = \$length // @fact.first: * > \$n, :k;    my \$f;    [ @fact[^\$i].reverse.map: { (\$n, \$f) = \$n.polymod(\$_); \$f } ]} sub fpermute (@a is copy, *@f) { (^@f).map: { @a[\$_ .. \$_ + @f[\$_]].=rotate(-1) }; @a } put "Part 1: Generate table";put \$_.&base('F', 3).join('.') ~ ' -> ' ~ [0,1,2,3].&fpermute(\$_.&base('F', 3)).join for ^24; put "\nPart 2: Compare 11! to 11! " ~ '¯\_(ツ)_/¯';# This is kind of a weird request. Since we don't actually need to _generate_# the permutations, only _count_ them: compare count of 11! vs count of 11!put "11! === 11! : {11! === 11!}"; put "\nPart 3: Generate the given task shuffles";my \Ω = <A♠ K♠ Q♠ J♠ 10♠ 9♠ 8♠ 7♠ 6♠ 5♠ 4♠ 3♠ 2♠ A♥ K♥ Q♥ J♥ 10♥ 9♥ 8♥ 7♥ 6♥ 5♥ 4♥ 3♥ 2♥         A♦ K♦ Q♦ J♦ 10♦ 9♦ 8♦ 7♦ 6♦ 5♦ 4♦ 3♦ 2♦ A♣ K♣ Q♣ J♣ 10♣ 9♣ 8♣ 7♣ 6♣ 5♣ 4♣ 3♣ 2♣>; my @books = <    39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0    51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1>; put "Original deck:";put Ω.join; put "\n\$_\n" ~ Ω[(^Ω).&fpermute(\$_.split: '.')].join for @books; put "\nPart 4: Generate a random shuffle";my @shoe = (+Ω … 2).map: { (^\$_).pick };put @shoe.join('.');put Ω[(^Ω).&fpermute(@shoe)].join; put "\nSeems to me it would be easier to just say: Ω.pick(*).join";put Ω.pick(*).join;`
Output:
```Part 1: Generate table
0.0.0 -> 0123
0.0.1 -> 0132
0.1.0 -> 0213
0.1.1 -> 0231
0.2.0 -> 0312
0.2.1 -> 0321
1.0.0 -> 1023
1.0.1 -> 1032
1.1.0 -> 1203
1.1.1 -> 1230
1.2.0 -> 1302
1.2.1 -> 1320
2.0.0 -> 2013
2.0.1 -> 2031
2.1.0 -> 2103
2.1.1 -> 2130
2.2.0 -> 2301
2.2.1 -> 2310
3.0.0 -> 3012
3.0.1 -> 3021
3.1.0 -> 3102
3.1.1 -> 3120
3.2.0 -> 3201
3.2.1 -> 3210

Part 2: Compare 11! to 11! ¯\_(ツ)_/¯
11! === 11! : True

Part 3: Generate the given task shuffles
Original deck:
A♠K♠Q♠J♠10♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥10♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦10♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣10♣9♣8♣7♣6♣5♣4♣3♣2♣

39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0
A♣3♣7♠4♣10♦8♦Q♠K♥2♠10♠4♦7♣J♣5♥10♥10♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦

51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1
2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣10♥K♣10♣5♦7♥10♦3♠8♥10♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠

Part 4: Generate a random shuffle
47.9.46.16.28.8.36.27.29.1.9.27.1.16.21.22.28.34.30.8.19.27.18.22.3.25.15.20.12.14.8.9.11.1.4.0.3.5.4.2.2.10.8.1.6.1.2.4.1.2.1
6♣5♠5♣10♥10♦6♠K♣9♦6♦K♠2♠5♦Q♠5♥Q♦8♦J♣2♣8♣A♥K♦9♣A♦2♦9♠4♣3♥A♣7♥2♥Q♥9♥4♥J♠4♠A♠3♠8♥J♥7♠K♥3♣10♣8♠Q♣6♥7♦7♣J♦3♦4♦10♠

Seems to me it would be easier to just say: Ω.pick(*).join
5♦3♠8♦10♦2♥7♠7♦Q♦A♠5♣8♣Q♠4♠2♦K♦5♠Q♥7♣10♠2♠K♠J♣9♣3♣4♥3♥4♦3♦Q♣2♣4♣J♦9♠A♣J♠10♣6♣9♦6♠10♥6♥9♥J♥7♥K♥A♦8♠A♥5♥8♥K♣6♦```

## Phix

`function fperm(sequence fbn, omega)integer m=0    for i=1 to length(fbn) do        integer g = fbn[i]        if g>0 then            omega[m+1..m+g+1] = omega[m+g+1]&omega[m+1..m+g]        end if        m += 1    end for    return omegaend function function factorial_base_numbers(integer size, bool countOnly)-- translation of Go    sequence results = {}, res = repeat(0,size)    integer count = 0, n = 0    while true do        integer radix = 2, k = n        while k>0 do            if not countOnly            and radix <= size+1 then                res[size-radix+2] = mod(k,radix)            end if            k = floor(k/radix)            radix += 1        end while        if radix > size+2 then exit end if        count += 1        if not countOnly then            results = append(results, res)        end if        n += 1    end while    return iff(countOnly?count:results)end function sequence fbns = factorial_base_numbers(3,false)for i=1 to length(fbns) do    printf(1,"%v -> %v\n",{fbns[i],fperm(fbns[i],{0,1,2,3})})end forprintf(1,"\n") integer count = factorial_base_numbers(10,true)printf(1,"Permutations generated = %d\n", count)printf(1,"  versus factorial(11) = %d\n", factorial(11)) procedure show_cards(sequence s)    printf(1,"\n")    for i=1 to length(s) do        integer c = s[i]-1        string sep = iff(mod(i,13)=0 or i=length(s)?"\n":" ")        puts(1,"AKQJT98765432"[mod(c,13)+1]&"SHDC"[floor(c/13)+1]&sep)    end forend procedure function rand_fbn51()    sequence fbn51 = repeat(0,51)    for i=1 to 51 do        fbn51[i] = rand(52-i)    end for    return fbn51end function sequence fbn51s = {{39,49, 7,47,29,30, 2,12,10, 3,29,37,33,17,12,31,29,                    34,17,25, 2, 4,25, 4, 1,14,20, 6,21,18, 1, 1, 1, 4,                     0, 5,15,12, 4, 3,10,10, 9, 1, 6, 5, 5, 3, 0, 0, 0},                   {51,48,16,22, 3, 0,19,34,29, 1,36,30,12,32,12,29,30,                    26,14,21, 8,12, 1, 3,10, 4, 7,17, 6,21, 8,12,15,15,                    13,15, 7, 3,12,11, 9, 5, 5, 6, 6, 3, 4, 0, 3, 2, 1},                   rand_fbn51()}for i=1 to length(fbn51s) do    show_cards(fperm(fbn51s[i],tagset(52)))end for`
Output:
```{0,0,0} -> {0,1,2,3}
{0,0,1} -> {0,1,3,2}
{0,1,0} -> {0,2,1,3}
{0,1,1} -> {0,2,3,1}
{0,2,0} -> {0,3,1,2}
{0,2,1} -> {0,3,2,1}
{1,0,0} -> {1,0,2,3}
{1,0,1} -> {1,0,3,2}
{1,1,0} -> {1,2,0,3}
{1,1,1} -> {1,2,3,0}
{1,2,0} -> {1,3,0,2}
{1,2,1} -> {1,3,2,0}
{2,0,0} -> {2,0,1,3}
{2,0,1} -> {2,0,3,1}
{2,1,0} -> {2,1,0,3}
{2,1,1} -> {2,1,3,0}
{2,2,0} -> {2,3,0,1}
{2,2,1} -> {2,3,1,0}
{3,0,0} -> {3,0,1,2}
{3,0,1} -> {3,0,2,1}
{3,1,0} -> {3,1,0,2}
{3,1,1} -> {3,1,2,0}
{3,2,0} -> {3,2,0,1}
{3,2,1} -> {3,2,1,0}

Permutations generated = 39916800
versus factorial(11) = 39916800

AC 3C 7S 4C TD 8D QS KH 2S TS 4D 7C JC
5H TH TC KC 2C 3H 5D JS 6S QC 5S KS AD
3D QH 8C 6D 9S 8S 4S 9H AS 6H 5C 2D 7H
8H 9C 6C 7D AH JD QD 9D 2H 3S JH 4H KD

2C 5C JH 4H JS AS 5H AC 6D QS 9C 3D QH
JC TH KC TC 5D 7H TD 3S 8H TS 7S 6H 5S
KH 4D AH 4C 2H 9D QC 8C 7D 6C 3H 6S 7C
2D JD 9H AD QD 8D 4S KD KS 3C 2S 8S 9S

JS 4H JD 9H 2C 9C 3C KH 9S TH 6D 5S 3H
2H 3S JH 5H QD 4C 7D 4S QC 7C TS 5C 6H
KS 5D QH 2S AD AC 7S QS TC JC 7H 6C 8H
KC 9D 4D 8D KD 6S TD AH 8C 2D 8S 3D AS
```

## Python

` """ http://rosettacode.org/wiki/Factorial_base_numbers_indexing_permutations_of_a_collection https://en.wikipedia.org/wiki/Factorial_number_system """ import math def apply_perm(omega,fbn):    """     omega contains a list which will be permuted (scrambled)    based on fbm.     fbm is a list which represents a factorial base number.     This function just translates the pseudo code in the     Rosetta Code task.     """    for m in range(len(fbn)):        g = fbn[m]        if g > 0:            # do rotation            # save last number            new_first = omega[m+g]            # move numbers right            omega[m+1:m+g+1] = omega[m:m+g]            # put last number first            omega[m] = new_first     return omega def int_to_fbn(i):    """     convert integer i to factorial based number     """    current = i    divisor = 2    new_fbn = []    while current > 0:        remainder = current % divisor        current = current // divisor        new_fbn.append(remainder)        divisor += 1     return list(reversed(new_fbn)) def leading_zeros(l,n):   """    If list l has less than n elements returns l with enough 0 elements   in front of the list to make it length n.    """   if len(l) < n:       return(([0] * (n - len(l))) + l)   else:       return l def get_fbn(n):    """     Return the n! + 1 first Factorial Based Numbers starting with zero.     """    max = math.factorial(n)     for i in range(max):        # from Wikipedia article        current = i        divisor = 1        new_fbn = int_to_fbn(i)        yield leading_zeros(new_fbn,n-1) def print_write(f, line):    """     prints to console and    output file f     """    print(line)    f.write(str(line)+'\n')      def dot_format(l):    """    Take a list l that is a factorial based number    and returns it in dot format.     i.e. [0, 2, 1] becomes 0.2.1    """    # empty list    if len(l) < 1:        return ""    # start with just first element no dot    dot_string = str(l[0])    # add rest if any with dots    for e in l[1:]:        dot_string += "."+str(e)     return dot_string def str_format(l):    """    Take a list l and returns a string    of those elements converted to strings.    """    if len(l) < 1:        return ""     new_string = ""     for e in l:        new_string += str(e)     return new_string  with open("output.html", "w", encoding="utf-8") as f:    f.write("<pre>\n")     # first print list     omega=[0,1,2,3]     four_list = get_fbn(4)     for l in four_list:        print_write(f,dot_format(l)+' -> '+str_format(apply_perm(omega[:],l)))     print_write(f," ")     # now generate this output:    #    # Permutations generated = 39916800    # compared to 11! which  = 39916800      num_permutations = 0     for p in get_fbn(11):        num_permutations += 1        if num_permutations % 1000000 == 0:            print_write(f,"permutations so far = "+str(num_permutations))     print_write(f," ")    print_write(f,"Permutations generated = "+str(num_permutations))    print_write(f,"compared to 11! which  = "+str(math.factorial(11)))     print_write(f," ")       """     u"\u2660" - spade     u"\u2665" - heart     u"\u2666" - diamond     u"\u2663" - club     """     shoe = []     for suit in [u"\u2660",u"\u2665",u"\u2666",u"\u2663"]:        for value in ['A','K','Q','J','10','9','8','7','6','5','4','3','2']:            shoe.append(value+suit)     print_write(f,str_format(shoe))     p1 = [39,49,7,47,29,30,2,12,10,3,29,37,33,17,12,31,29,34,17,25,2,4,25,4,1,14,20,6,21,18,1,1,1,4,0,5,15,12,4,3,10,10,9,1,6,5,5,3,0,0,0]     p2 = [51,48,16,22,3,0,19,34,29,1,36,30,12,32,12,29,30,26,14,21,8,12,1,3,10,4,7,17,6,21,8,12,15,15,13,15,7,3,12,11,9,5,5,6,6,3,4,0,3,2,1]     print_write(f," ")    print_write(f,dot_format(p1))    print_write(f," ")    print_write(f,str_format(apply_perm(shoe[:],p1)))     print_write(f," ")    print_write(f,dot_format(p2))    print_write(f," ")    print_write(f,str_format(apply_perm(shoe[:],p2)))     # generate random 51 digit factorial based number     import random     max = math.factorial(52)     random_int = random.randint(0, max-1)     myperm = leading_zeros(int_to_fbn(random_int),51)     print(len(myperm))     print_write(f," ")    print_write(f,dot_format(myperm))    print_write(f," ")    print_write(f,str_format(apply_perm(shoe[:],myperm)))     f.write("</pre>\n")  `
Output:
```0.0.0 -> 0123
0.0.1 -> 0132
0.1.0 -> 0213
0.1.1 -> 0231
0.2.0 -> 0312
0.2.1 -> 0321
1.0.0 -> 1023
1.0.1 -> 1032
1.1.0 -> 1203
1.1.1 -> 1230
1.2.0 -> 1302
1.2.1 -> 1320
2.0.0 -> 2013
2.0.1 -> 2031
2.1.0 -> 2103
2.1.1 -> 2130
2.2.0 -> 2301
2.2.1 -> 2310
3.0.0 -> 3012
3.0.1 -> 3021
3.1.0 -> 3102
3.1.1 -> 3120
3.2.0 -> 3201
3.2.1 -> 3210

permutations so far = 1000000
permutations so far = 2000000
permutations so far = 3000000
permutations so far = 4000000
permutations so far = 5000000
permutations so far = 6000000
permutations so far = 7000000
permutations so far = 8000000
permutations so far = 9000000
permutations so far = 10000000
permutations so far = 11000000
permutations so far = 12000000
permutations so far = 13000000
permutations so far = 14000000
permutations so far = 15000000
permutations so far = 16000000
permutations so far = 17000000
permutations so far = 18000000
permutations so far = 19000000
permutations so far = 20000000
permutations so far = 21000000
permutations so far = 22000000
permutations so far = 23000000
permutations so far = 24000000
permutations so far = 25000000
permutations so far = 26000000
permutations so far = 27000000
permutations so far = 28000000
permutations so far = 29000000
permutations so far = 30000000
permutations so far = 31000000
permutations so far = 32000000
permutations so far = 33000000
permutations so far = 34000000
permutations so far = 35000000
permutations so far = 36000000
permutations so far = 37000000
permutations so far = 38000000
permutations so far = 39000000

Permutations generated = 39916800
compared to 11! which  = 39916800

A♠K♠Q♠J♠10♠9♠8♠7♠6♠5♠4♠3♠2♠A♥K♥Q♥J♥10♥9♥8♥7♥6♥5♥4♥3♥2♥A♦K♦Q♦J♦10♦9♦8♦7♦6♦5♦4♦3♦2♦A♣K♣Q♣J♣10♣9♣8♣7♣6♣5♣4♣3♣2♣

39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0

A♣3♣7♠4♣10♦8♦Q♠K♥2♠10♠4♦7♣J♣5♥10♥10♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦

51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1

2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣10♥K♣10♣5♦7♥10♦3♠8♥10♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠

35.21.48.20.4.1.5.41.3.1.25.34.30.4.25.1.11.29.28.4.5.29.17.28.0.18.14.19.20.1.1.4.19.6.2.6.9.5.8.3.10.10.7.1.7.3.0.3.2.0.0

5♦6♥3♣7♥10♠K♠7♠6♣9♠Q♠8♦10♣A♣5♠6♦J♠9♥9♣J♣3♠A♥4♣J♦2♣A♠7♦K♦2♦Q♣6♠4♠J♥5♣5♥K♥3♥10♦4♥9♦10♥8♣7♣4♦2♠K♣2♥8♠Q♦A♦Q♥8♥3♦
```

## zkl

`fcn fpermute(omega,num){  // eg (0,1,2,3), (0,0,0)..(3,2,1)   omega=omega.copy(); 	  // omega gonna be mutated   foreach m,g in ([0..].zip(num)){ if(g) omega.insert(m,omega.pop(m+g)) }   omega}`
Part 1, Generate permutation table:
`foreach a,b,c in (4,3,2){   println("%d.%d.%d --> %s".fmt(a,b,c, fpermute(T(0,1,2,3),T(a,b,c)).concat()));}`
Output:
```0.0.0 --> 0123
0.0.1 --> 0132
0.1.0 --> 0213
0.1.1 --> 0231
0.2.0 --> 0312
0.2.1 --> 0321
1.0.0 --> 1023
1.0.1 --> 1032
1.1.0 --> 1203
1.1.1 --> 1230
1.2.0 --> 1302
1.2.1 --> 1320
2.0.0 --> 2013
2.0.1 --> 2031
2.1.0 --> 2103
2.1.1 --> 2130
2.2.0 --> 2301
2.2.1 --> 2310
3.0.0 --> 3012
3.0.1 --> 3021
3.1.0 --> 3102
3.1.1 --> 3120
3.2.0 --> 3201
3.2.1 --> 3210
```
Part 3, Generate the given task shuffles:
`deck:=List();foreach s,c in ("\u2660 \u2665 \u2666 \u2663".split(),                 "A K Q J 10 9 8 7 6 5 4 3 2".split()){ deck.append(c+s) }books:=List(   "39.49.7.47.29.30.2.12.10.3.29.37.33.17.12.31.29.34.17.25.2.4.25.4.1.14.20.6.21.18.1.1.1.4.0.5.15.12.4.3.10.10.9.1.6.5.5.3.0.0.0",   "51.48.16.22.3.0.19.34.29.1.36.30.12.32.12.29.30.26.14.21.8.12.1.3.10.4.7.17.6.21.8.12.15.15.13.15.7.3.12.11.9.5.5.6.6.3.4.0.3.2.1")   .apply(fcn(s){ s.split(".").apply("toInt") });foreach book in (books){ println(fpermute(deck,book).concat("")); }`
Output:
```A♣3♣7♠4♣10♦8♦Q♠K♥2♠10♠4♦7♣J♣5♥10♥10♣K♣2♣3♥5♦J♠6♠Q♣5♠K♠A♦3♦Q♥8♣6♦9♠8♠4♠9♥A♠6♥5♣2♦7♥8♥9♣6♣7♦A♥J♦Q♦9♦2♥3♠J♥4♥K♦
2♣5♣J♥4♥J♠A♠5♥A♣6♦Q♠9♣3♦Q♥J♣10♥K♣10♣5♦7♥10♦3♠8♥10♠7♠6♥5♠K♥4♦A♥4♣2♥9♦Q♣8♣7♦6♣3♥6♠7♣2♦J♦9♥A♦Q♦8♦4♠K♦K♠3♣2♠8♠9♠
```
Part 4, Generate a random shuffle:
`r:=[52..2,-1].pump(List,(0).random);println(r.concat("."),"\n",fpermute(deck,r).concat(""));`
Output:
```36.21.48.31.19.37.16.39.43.1.27.23.30.22.14.32.31.2.27.11.5.24.28.20.23.20.17.19.23.13.11.12.3.12.1.0.11.1.8.10.6.2.8.3.7.1.1.4.2.2.1
4♦6♥3♣8♦8♥Q♣J♥8♣2♣K♠9♦K♦2♦A♦Q♥9♣10♣J♠A♣A♥7♠3♦5♣10♦K♣7♦2♥6♦4♣7♥10♥5♥9♠3♥Q♠A♠J♦8♠4♥J♣K♥5♠7♣3♠6♣6♠4♠5♦9♥Q♦2♠10♠
```