Write a simple but impactful script

Basic challenge (simple): Write a script that produces all possible 4-digit numbers (0000...9999), then put them into a random order and save the output into a text file. Make sure you include leading zeroes where necessary and make also sure that each number is on a separate line in the text file.

Bonus challenge (for daring programmers only): Do the basic challenge and then do the following: Call the generated file leaked_pins.txt, and email it to one of your co-workers. In the description of the email, say that all the PIN numbers have been leaked, and they should be cautious and check, whether their PIN is contained in the file or not.

Share your code below. If any of you tries the bonus challenge, I am happy to hear any stories :)

Comments

[Jason Rogers †]

Just coming across this. I like finding and using old gems. For this, jot does just great.

jot -w %04d 9999 | shuf > /path/to/pins.txt

Or for those on a Mac using GNU coreutils (probably from brew), you'd use gshuf instead of shuf:

jot -w %04d 9999 | gshuf > /path/to/pins.txt

Of course, Ruby is just as elegant:

ruby -e 'puts ("0000"..."9999").to_a.shuffle' > /path/to/pins.txt

... but on my machine the Ruby solution is about 95% slower than the jot version: 148ms vs. 8ms, respectively.

[Ben Sinclair]

Vim/Bash:

9998O<esc>:%s/^/\=printf('%04d',line('.'))/<cr>:%!shuf<cr>:w leaked-pins.txt

[lchvdlch]

AWK:

awk 'BEGIN{for(i=0;i<10000;i++){N[i]=sprintf("%04d",i)};while(i){j=int(10000*rand());if(N[j]){print N[j];delete N[j];i--}}}' > leaked_pins.txt

[Quainor]

Love the bonus challenge!
Sent such a list to a friend working for a bank years ago.
This made it to the board of directors within minutes.
Still laughing and gasping - almost can't believe this impact :-D.

[Mara Sophie Grosch (LittleFox)]

Hacky Perl/sh oneliner

perl -e '@v=("0000".."9999"); %x; print map { do { $i=int(rand(@v)); } while($x{$i}); $x{$i}=1; $v[$i] . "\n"} @v;' > hacked_pins.txt

Generates a list of pins (@v) and then selects a random entry for every entry in the list (hacky use of map). %x is used to mark which entries already have been returned.

[Vincent Guarnaccia]

seq --equal-width 0 1 9999 | sort --random-sort > result.txt

[Vincent Guarnaccia]

Easier to read and works with embedded Linux systems (BusyBox):

seq -w 0 1 9999 | shuf > result.txt

[Ryan Palo]

I didn't know this for a long time, but you can use strings to build ranges in Ruby as well, avoiding the need for any fancy padding with zeros!

pins = ("0000".."9999").to_a.shuffle.join("\n")
File.open("pins.txt", "w") { |f| f << pins }

[Philippe Back]

Pharo

(file :='leaked_pins.txt' asFileReference) writeStreamDo: [ :s |
(0 to: 9999) shuffled do: [ :n | s << (n printPaddedWith: $0 to: 4); cr ]].

SMTPClient 
deliverMailFrom: '[e-mail]' 
to: { '[e-mail]' }
text: ('All the PIN numbers have been leaked, and you should be cautious and check, whether your PIN is contained in the file. ', file contents)
usingServer: 'somereplay.world.net'

[Dylan Paulus]

Clojure?

 (spit "./hacks.txt" 
       (clojure.string/join "\n" 
            (shuffle 
                (map 
                   #(format "%04d" %) 
                    (range 0 10000)))))

[Rafael Dowling Goodman]

F#

do
    let rnd = System.Random()
    use file = System.IO.File.CreateText("leaked_pins.txt")

    [0..9999]
    |> Seq.sortBy (fun _ -> rnd.Next())
    |> Seq.iter (fprintfn file "%04d")