Pseudo-random numbers/Middle-square method: Difference between revisions

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Line 1: {{task}} {{Wikipedia\|Middle-square method\|en}} ~~;[https://en.m.wikipedia.org/wiki/Middle-square_method Middle-square_method] Generator~~ ; The Method: To generate a sequence of n-digit pseudorandom numbers, an n-digit starting value is created and squared, producing a 2n-digit number. If the result has fewer than 2n digits, leading zeroes are added to compensate. The middle n digits of the result would be the next number in the sequence and returned as the result. This process is then repeated to generate more numbers. Line 30: * Show your output here, on this page. =={{header\|11l}}== {{trans\|Python}} <syntaxhighlight lang="11l"> F random() V :seed = 675248 :seed = Int(String(Int64(:seed) ^ 2).zfill(12)[3 .+ 6]) R :seed L 5 print(random()) </syntaxhighlight> {{out}} <pre> 959861 333139 981593 524817 432883 </pre> =={{header\|AArch64 Assembly}}== Line 122 ⟶ 144: 432883 </pre> =={{header\|Ada}}== <syntaxhighlight lang="ada">with Ada.Text_IO; use Ada.Text_IO; Line 187 ⟶ 210: {{output}} <syntaxhighlight lang="applescript">{959861, 333139, 981593, 524817, 432883}</syntaxhighlight> =={{header\|Amazing Hopper}}== Flavour BASICO. <p>Version 1:</p> <syntaxhighlight lang="c"> #include <basico.h> algoritmo s=675248, i=4 iterar #( s = int(s ^2 / 1000 % 1000000) ) s, NL, imprimir mientras ' i-- ' terminar </syntaxhighlight> {{out}} <pre> 959861 333139 981593 524817 432883 </pre> <p>Version 2:</p> <syntaxhighlight lang="c"> #include <basico.h> algoritmo s=675248, i=5 iterar grupo( --i, i, #( s = int(s ^2 / 1000 % 1000000) ) \ s, NL, imprimir ) terminar </syntaxhighlight> {{out}} <pre> idem. </pre> <p>Version 3:</p> <syntaxhighlight lang="c"> #include <basico.h> algoritmo s=675248, i=5 iterar grupo( --i, i, #( int(s ^2 / 1000 % 1000000) ) \ ---copiar en 's'---, NL, imprimir ) terminar </syntaxhighlight> {{out}} <pre> idem. </pre> <p>Version 4:</p> <syntaxhighlight lang="c"> #include <basico.h> algoritmo s=675248, i=4 rareti( i, #( int(s ^2 / 1000 % 1000000) ) \ ---copiar en 's'---, NL ); entonces imprime terminar </syntaxhighlight> {{out}} <pre> idem. </pre> =={{header\|ARM Assembly}}== Line 323 ⟶ 411: 432883 </pre> =={{header\|Arturo}}== <syntaxhighlight lang="arturo">seed: 675248 rand: function => [ let 'seed <= ((seed^2) / 1000) % 1000000 ] do.times: 5 -> print rand</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883</pre> =={{header\|AWK}}== <syntaxhighlight lang="awk"> Line 351 ⟶ 457: 5: 432883 </pre> =={{header\|BASIC}}== ==={{header\|BASIC256}}=== <syntaxhighlight lang="vb">global semilla semilla = 675248 for i = 1 to 5 print i; ": "; Random() next i end function Random() semilla = floor((semillasemilla/1e3) mod 1e6) return int(semilla) end function</syntaxhighlight> {{out}} <pre>1: 959861 2: 333139 3: 981593 4: 524817 5: 432883</pre> ==={{header\|Chipmunk Basic}}=== {{works with\|Chipmunk Basic\|3.6.4}} <syntaxhighlight lang="qbasic">10 semilla = 675248 20 for i = 1 to 5 30 print i;": ";semilla 31 semilla = ((semillasemilla)/1000) mod 1000000 40 next i</syntaxhighlight> ==={{header\|FreeBASIC}}=== <syntaxhighlight lang="freebasic">Dim Shared seed As Integer = 675248 Dim i As Integer Declare Function Rand As Integer For i = 1 To 5 Print Rand Next i Sleep Function Rand As Integer Dim s As String s = Str(seed ^ 2) Do While Len(s) <> 12 s = "0" + s Loop seed = Val(Mid(s, 4, 6)) Rand = seed End Function </syntaxhighlight> ==={{header\|PureBasic}}=== <syntaxhighlight lang="purebasic">Procedure.i MSRandom() Static.i seed=675248 seed = (seedseed/1000)%1000000 ProcedureReturn seed EndProcedure If OpenConsole() For i=1 To 5 : PrintN(Str(i)+": "+Str(MSRandom())) : Next Input() EndIf</syntaxhighlight> {{out}} <pre>1: 959861 2: 333139 3: 981593 4: 524817 5: 432883</pre> ==={{header\|uBasic/4tH}}=== {{trans\|C}} <syntaxhighlight lang="text">If Info("wordsize") < 64 Then Print "This needs a 64-bit uBasic" : End s = 675248 For i = 1 To 5 Print Set(s, FUNC(_random(s))) Next End _random Param (1) : Return (a@a@/1000%1000000)</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883 0 OK, 0:140 </pre> ==={{header\|Visual Basic}}=== {{trans\|FreeBASIC}} {{works with\|Visual Basic\|5}} {{works with\|Visual Basic\|6}} <syntaxhighlight lang="vb">Option Explicit Dim seed As Long Sub Main() Dim i As Integer seed = 675248 For i = 1 To 5 Debug.Print Rand Next i End Sub Function Rand() As Variant Dim s As String s = CStr(seed ^ 2) Do While Len(s) <> 12 s = "0" + s Loop seed = Val(Mid(s, 4, 6)) Rand = seed End Function</syntaxhighlight> {{out}} As expected. ==={{header\|Yabasic}}=== <syntaxhighlight lang="vb">semilla = 675248 for i = 1 to 5 print i, ": ", Random() next i end sub Random() semilla = floor(mod(((semillasemilla)/1e3), 1e6)) return int(semilla) end sub</syntaxhighlight> {{out}} <pre>1: 959861 2: 333139 3: 981593 4: 524817 5: 432883</pre> =={{header\|bc}}== <syntaxhighlight lang="bc">s = 675248 define r() { s = s s / 1000 % 1000000 return(s) } for (i = 0; i != 5; ++i) r()</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883</pre> =={{header\|BQN}}== <syntaxhighlight lang="bqn">1e6 \|⟜(⌊∘÷⟜1e3 ×˜)⍟(1+↕5) 675248</syntaxhighlight> Or: <syntaxhighlight lang="bqn">675248 (1e6 \| ×˜⊸(⌊÷))` 5 ⥊ 1e3</syntaxhighlight> {{out}} <pre>⟨ 959861 333139 981593 524817 432883 ⟩</pre> =={{header\|C}}== Line 366 ⟶ 625: }</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883</pre> =={{header\|C++}}== Line 471 ⟶ 730: 524817 432883 </pre> =={{header\|Delphi}}== {{works with\|Delphi\|6.0}} {{libheader\|SysUtils,StdCtrls}} <syntaxhighlight lang="Delphi"> var Seed: int64 = 675248; function MiddleSquareRandom: int64; var S: string; begin S:=IntToStr(Seed * Seed); while Length(S)<12 do S:='0'+S; Seed:=StrToInt(MidStr(S, 4, 6)); Result:=Seed; end; procedure ShowMiddleSqrRandom(Memo: TMemo); var I: integer; begin for I:=1 to 5 do Memo.Lines.Add(IntToStr(MiddleSquareRandom)); end; </syntaxhighlight> {{out}} <pre> 959861 333139 981593 524817 432883 Elapsed Time: 5.610 ms. </pre> =={{header\|dc}}== <syntaxhighlight lang="dc">675248 5 sn [d * 1000 / 1000000 %] sr [lr x p ln 1 - d sn 0 <l] d sl x</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883</pre> =={{header\|EasyLang}}== <syntaxhighlight lang="text"> global seed . seed = 675248 func rand . strSeed$ = seed s$ = seed * seed while not len s$ = len strSeed$ * 2 s$ = "0" & s$ . seed = number substr s$ (len strSeed$ / 2 + 1) len strSeed$ randNum = seed return randNum . for i = 1 to 5 print rand . </syntaxhighlight> {{out}} <pre> 959861 333139 981593 524817 432883 </pre> =={{header\|EDSAC order code}}== EDSAC (including its name) was inspired by John von Neumann's "First Draft of a Report on the EDVAC", so a task in his honour ought to have an EDSAC solution. As noted in the Discussion, the sequence in the task description falls into a repetition of 625000. <syntaxhighlight lang="edsac"> [Von Neumann's middle-square pseudo-random number generator, for Rosetta Code. EDSAC program, Initial Orders 2.] [Arrange the storage] T46K P56F [N parameter: library subroutine P7 to print integer] T47K P134F [M parameter: main routine] T51K P92F [G parameter: generator for pseudo-random numbers] [This version of von Neumann's PRNG uses values in the range 0..999999. Initialize: Call 0G with seed in 0D. Next term: Call 1G; term is returned in 0D. 41 storage locations, load at even address. Workspace 4D.] E25K TG GK G10@ [jump to initialize the generator] G15@ [jump to return the next term in 0D] [Instructions to the loader - not executed at runtime] T2#Z PF [ensure sandwich bit between 2@ and 3@ is zero] T4#Z PF T6#Z PF [same for 4@ and 5@, 6@ and 7@] T2Z [resume normal loading at 2@] [Constants] [2] M1667D I1208F [2^29/10^9, near enough (see note at end)] [4] G1327D I393F [2^9/10^3, near enough (see note at end)] [10^9/2^34 can't be stored using pseudo-orders, so store its negative instead.] [6] D768F V140D [-10^9/2^34] [Variable] [8] PF PF [state of PRNG] [Initialize the PRNG. Caller passes seed in 0D.] [10] A3F T14@ [plant return link as usual] AD T8#@ [copy seed to state] [14] ZF [(planted) jump back to caller] [Return the next value in 0D. Outline: Let X = state, 0 <= X <= 999999, fits into 20 bits. Calculate Y = X^2 div 10^9. Deduce Z = X^2 mod 10^9 = X^2 - (10^9)Y The next state is Z div 10^3. See note at end of program for details of integer division.] [15] A3F T40@ [plant return link as usual] A8#@ [acc := X/2^34] L32F L32F [shift 7 + 7 left, acc := X/2^20] T4D [store X/2^20 in 4D] H4D V4D [square, acc := (X^2)/2^40] [Here acc holds sign bit plus 40 binary places of (X^2)/2^40.] [On storing acc in a 35-bit location, the low 6 bits are lost.] [This doesn't matter, because 2^6 divides 10^9, so we can evaluate] [X^2 div 10^9 = (X^2 div 2^6) div (10^9/2^6).] TD [0D now represents X^2 div 2^6] H2#@ [mult reg := 2^29/10^9 nearly] VD [Commented out: code for 35-bit operations, following note at end. \|R 1024 F\| \|R 512 F\| shift 23 right, as in note \|T D\| 0D := Y/2^34 where Y = X^2 div 10^9 \|H neg_10_9 #@\| \|V D\| times -10^9/2^34, acc := -10^9Y/2^68 We need to shift 34 left to restore the scaling after multiplication \|L 1024 F\| \|L 1024 F\| \|L 4 F\| first shift 28 left, acc := 10^9Y/2^40] [More efficient code, possible because Y (= X^2 div 10^9) fits into a 17-bit location. Shifting is 18 less than the 35-bit version.] R8F [shift 5 right] TF [0F := Y/2^16] H6#@ VF [times -10^9/2^34, acc := -10^9Y/2^50] [We need to shift 16 left to restore the scaling after multiplication] L256F [first shift 10 left, acc := 10^9Y/2^40] H4D V4D [4D = X/2^20 from above, so acc := (X^2 - 10^9Y)/2^40] L16F TD [shift 6 more left; 0D := Z/2^34 where Z = X^2 - 10^9Y] H4#@ [mult reg := 2^9/10^3 nearly] VD R128F [shift 9 right] U8#@ [save next state u] TD [also return next state to caller in 0D] [40] ZF [(planted) jump back to caller] [------------------------------------------------------------------------] E25K TM GK [M parameter, main routine. Load at even address.] T#Z PF [clear 35-bit value at relative locations 0 & 1, including the middle ("sandwich") bit] TZ [resume normal loading at relative location 0] [We could read the seed and number of terms from a separate tape, but that would require another subroutine.] [0] G296F V2046D [-675248 (negative of seed, cf -10^9 above)] [2] P211F [number of terms, in the address field] [3] PF [index of term] [4] #F [teleprinter, set figures mode] [5] !F [space] [6] &F [line feed] [7] @F [carriage return] [8] K4096F [null] [9] PF [Enter with acc = 0] [10] O4@ [set teleprinter to figures] S#@ TD [pass seed in 0D] [13] A13@ GG [call subroutine to initilaize PRNG] T3@ [index := 0] [Head of loop; here with acc = 0] [16] TD [clear parameter for print subroutine] A3@ S2@ [printed enough terms?] E34@ [if so, jump to exit] A2@ [restore acc after test] A2F U3@ [update index] RD TF [right-justify for printing; pass in 0D] [25] A25@ GN [call subroutine to print index] [27] A27@ G1G [call PRNG; returns next term in 0D] [29] A29@ GN [print term; clears acc.] O7@ O6@ [print CR, LF] E16@ [loop back for next term] [34] O8@ [print null to flush printer buffer] ZF [stop] [----------------------------------------------------------------------] E25K TN [N parameter, print subroutine] [Library subroutine P7, prints long strictly positive integer in 0D.] [10 characters, right justified, padded left with spaces.] [Even address; 35 storage locations; working position 4D.] GKA3FT26@H28#@NDYFLDT4DS27@TFH8@S8@T1FV4DAFG31@SFLDUFOFFFSF L4FT4DA1FA27@G11@XFT28#ZPFT27ZP1024FP610D@524D!FO30@SFL8FE22@ [----------------------------------------------------------------------] E25K TM GK [M parameter again] E10Z [start execution at relative address] PF [ Note: Integer division by a constant on EDSAC. Some programs require the integer quotient N div D, where N is variable and D is constant throughout the program. Since EDSAC had hardware multiplication but not hardware division, it makes sense to store 1/D and multiply N by that. This note describes one way of doing this, and finds a sufficient condition on N for rounding errors not to affect the result. It's assumed that 35-bit integers are used, so that an integer N is represented by N(2^-34); also that N and D are positive. Let k be the greatest integer such that 2^k < D. We store a multiplier 2^k/D, rounded up to an integer multiple of 2^-34. Let the stored multiplier be 2^k/D + f(2^-34), where 0 <= f < 1. Let N = qD + r, where q is an integer and 0 <= r < D. To find the integer quotient q, multiply N(2^-34) by the stored multiplier and shift right by k bits. This gives (2^-34)(q + r/D + Nf(2^(-k -34))) in the accumulator. If the top 35 bits of the accumulator are stored in memory, the value stored will be q(2^-34), provided r/D + Nf(2^(-k-34)) < 1. Since r <= D - 1, a sufficient condition for this is Nf(2^(-k-34)) < 1/D which is equivalent to N < (2^k/D)(2^34/f). () Examples from the middle-square program: (1) D = 10^9/2^6. Then k = 23 and 2^k/D = 0.536870912. Also 2^(k+34)/D = 2^63/10^9 = 9223372036.854775808 so that the stored multiplier is 9223372037(2^-34) and f = 0.145224192. Since f < 2^k/D, the condition () is satisfied for all N < 2^34. (2) D = 10^3. Then k = 9 and 2^k/D = 0.512. Also 2^(k+34)/D = 2^43/10^3 = 8796093022.208 so that the stored multiplier is 8796093023(2^-34) and f = 0.792. The condition () becomes N < 1.11(10^10) (approx), which is satisfied in this program because N < 10^9. ] </syntaxhighlight> {{out}} <pre> 1 959861 2 333139 3 981593 4 524817 5 432883 [...] 207 437510 208 415000 209 225000 210 625000 211 625000 </pre> Line 515 ⟶ 1,020: {{out}} <pre>959861 333139 981593 524817 432883 ok</pre> ~~=={{header\|FreeBASIC}}==~~ ~~<syntaxhighlight lang="freebasic">Dim Shared seed As Integer = 675248~~ ~~Dim i As Integer~~ ~~Declare Function Rand As Integer~~ ~~For i = 1 To 5~~ ~~Print Rand~~ ~~Next i~~ ~~Sleep~~ ~~Function Rand As Integer~~ ~~Dim s As String~~ ~~s = Str(seed ^ 2)~~ ~~Do While Len(s) <> 12~~ ~~s = "0" + s~~ ~~Loop~~ ~~seed = Val(Mid(s, 4, 6))~~ ~~Rand = seed~~ ~~End Function~~ ~~</syntaxhighlight>~~ =={{header\|Go}}== Line 577 ⟶ 1,061: =={{header\|J}}== <syntaxhighlight lang="j">(_6 {. _3 }. ])&.:(10&#.^:_1)@(~) ^: (>: i. 6) 675248</syntaxhighlight> Or, shorter & faster: <syntaxhighlight lang="j">}. (1e6 1e3 {.@#: :)^:(< 7) 675248</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883 387691</pre> =={{header\|Java}}== <syntaxhighlight lang="java"> public final class MiddleSquareTask { public static void main(String[] aArgs) { MiddleSquare random = new MiddleSquare(675248); for ( int i = 0; i < 5; i++ ) { System.out.println(random.nextInt()); } } } final class MiddleSquare { public MiddleSquare(int aSeed) { final int length = String.valueOf(aSeed).length(); if ( length % 2 == 1 ) { throw new IllegalArgumentException("Seed must have an even number of digits"); } state = aSeed; divisor = (int) Math.pow(10, length / 2); modulus = (int) Math.pow(10, length); } public int nextInt() { state = ( ( state * state ) / divisor ) % modulus; return (int) state; } private long state; private final int divisor, modulus; } </syntaxhighlight> {{ out }} <pre> 959861 333139 981593 524817 432883 </pre> =={{header\|jq}}== Line 625 ⟶ 1,159: 432883 </pre> =={{header\|Lambdatalk}}== {{trans\|C}} <syntaxhighlight lang="Scheme"> {def W.fill {lambda {:v :n} {if {<= :n 0} then else :v{W.fill :v {- :n 1}}}}} -> W.fill {def W.pad {lambda {:n :size} {if {<= {W.length :n} :size} then :n{W.fill :size {- :size {W.length :n}}} else {W.slice 0 {- :size {W.length :n}} :n}}}} -> W.pad {def randoms {lambda {:s :n} {if {>= :n 0} then :s {randoms {W.pad {% {floor {/ {* :s :s} 1.e3}} 1.e6} 6} {- :n 1}} else}}} -> randoms {randoms 959861 4} -> 959861 333139 981593 524817 432883 </syntaxhighlight> =={{header\|Lua}}== <syntaxhighlight lang="lua">seed = 675248 function rnd () local s = tostring(seed * seed) while #s ~= 12 do s = "0" .. s end seed = tonumber(s:sub(4, 9)) return seed end for i = 1, 5 do print(rnd()) end </syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883</pre> =={{header\|Miranda}}== <syntaxhighlight lang="miranda">main :: [sys_message] main = [Stdout (lay (map show numbers))] where numbers = take 5 (randoms 6 seed) seed = 675248 randoms :: num->num->[num] randoms sz = tl . iterate (msq sz) msq :: num->num->num msq sz seed = sq div (10^(sz div 2)) mod 10^sz where sq = seed^2</syntaxhighlight> {{out}} <pre>959861 333139 981593 524817 432883</pre> =={{header\|Nim}}== Line 645 ⟶ 1,252: =={{header\|OCaml}}== <syntaxhighlight lang="ocaml">let random_seq seed = let next x = x * x / ~~1_000~~1000 mod ~~1_000_000~~1000_000 in Seq.iterate next (next seed) (* test ~~code~~ ) let () = random_seq 675248 \|> Seq.take 5 \|> Seq.iter (Printf.printf " %u")</syntaxhighlight> ~~let print_first5 sq =~~ ~~sq \|> Seq.take 5 \|> Seq.map string_of_int~~ ~~\|> List.of_seq \|> String.concat " " \|> print_endline~~ in ~~print_first5 (random_seq 675248)</syntaxhighlight>~~ {{out}} <pre> 959861 333139 981593 524817 432883</pre> =={{header\|Perl}}== Line 695 ⟶ 1,298: <span style="color: #008080;">end</span> <span style="color: #008080;">for</span> <!--</syntaxhighlight>--> ~~=={{header\|PureBasic}}==~~ ~~<syntaxhighlight lang="purebasic">Procedure.i MSRandom()~~ ~~Static.i seed=675248~~ ~~seed = (seedseed/1000)%1000000~~ ~~ProcedureReturn seed~~ ~~EndProcedure~~ ~~If OpenConsole()~~ ~~For i=1 To 5 : PrintN(Str(i)+": "+Str(MSRandom())) : Next~~ ~~Input()~~ ~~EndIf</syntaxhighlight>~~ ~~{{out}}~~ ~~<pre>1: 959861~~ ~~2: 333139~~ ~~3: 981593~~ ~~4: 524817~~ ~~5: 432883</pre>~~ =={{header\|Python}}== Line 718 ⟶ 1,303: def random(): global seed sseed = int(str(seed ** 2).zfill(12)[3:9]) ~~while len(s) != 12:~~ ~~s = "0" + s~~ ~~seed = int(s[3:9])~~ return seed for i_ in range(0,5): print(random()) </syntaxhighlight> Line 795 ⟶ 1,377: 432883 </pre> =={{header\|RPL}}== {{works with\|Halcyon Calc\|4.2.7}} {\| class="wikitable" ! RPL code ! Comment \|- \| ≪ SQ →STR '''WHILE''' DUP SIZE 12 ≠ '''REPEAT''' "0" SWAP + '''END''' 4 9 SUB STR→ ≫ ‘'''RMID'''’ STO ≪ 675248 1 5 '''START RMID NEXT''' ≫ ‘'''TASK'''’ STO \| '''RMID''' ''( seed -- seed )'' var s = str(seed * seed) do while not len(s) = 12 s = "0" + s end do seed = val(mid(s, 4, 6)) return seed \|} {{out}} <pre> 5: 959861 4: 333139 3: 981593 2: 524817 1: 432883 </pre> =={{header\|Ruby}}== <syntaxhighlight lang="ruby">def middle_square (seed) Line 824 ⟶ 1,443: </pre> =={{header\|~~uBasic/4tH~~Tcl}}== <syntaxhighlight lang="tcl">set seed 675248 ~~{{trans\|C}}~~ ~~<syntaxhighlight lang="text">If Info("wordsize") < 64 Then Print "This needs a 64-bit uBasic" : End~~ proc rnd {} { ~~s = 675248~~ ~~For~~ i = 1 Toglobal 5seed set s [expr {$seed * $seed}] ~~Print Set(s, FUNC(_random(s)))~~ while {[string length $s] ne 12} { ~~Next~~ set s [string cat 0 $s] } set seed [string range $s 3 8] return $seed } for {set i 0} {$i < 5} {incr i} { ~~End~~ puts [rnd] } ~~_random Param (1) : Return (a@a@/1000%1000000)</syntaxhighlight>~~ </syntaxhighlight> {{out}} <pre>959861 Line 841 ⟶ 1,465: 981593 524817 432883</pre> ~~0 OK, 0:140~~ ~~</pre>~~ =={{header\|UNIX Shell}}== Line 863 ⟶ 1,484: =={{header\|VBA}}== :''See [[Pseudo-random numbers/Middle-square method#Visual Basic\|Visual Basic]]'' ~~=={{header\|Visual Basic}}==~~ ~~{{trans\|FreeBASIC}}~~ ~~{{works with\|Visual Basic\|5}}~~ ~~{{works with\|Visual Basic\|6}}~~ ~~<syntaxhighlight lang="vb">Option Explicit~~ ~~Dim seed As Long~~ ~~Sub Main()~~ ~~Dim i As Integer~~ ~~seed = 675248~~ ~~For i = 1 To 5~~ ~~Debug.Print Rand~~ ~~Next i~~ ~~End Sub~~ ~~Function Rand() As Variant~~ ~~Dim s As String~~ ~~s = CStr(seed ^ 2)~~ ~~Do While Len(s) <> 12~~ ~~s = "0" + s~~ ~~Loop~~ ~~seed = Val(Mid(s, 4, 6))~~ ~~Rand = seed~~ ~~End Function</syntaxhighlight>~~ ~~{{out}}~~ ~~As expected.~~ =={{header\|Wren}}== <syntaxhighlight lang="~~ecmascript~~wren">var random = Fn.new { \|seed\| ((seed seed)/1e3).floor % 1e6 } var seed = 675248