Counting in bijective base 62

Question

The task is to generate all the strings from 'a' to '999' including upper case characters like so:

'a', 'b', 'c' ... 'y', 'z', 'A', 'B', 'C' ... 'Y', 'Z', '0', '1', 2' ... 
'8', '9', 'aa', 'ab', 'ac' ... 'az', 'aA', 'aB' ... 'aZ', 'a0' ... 'a9', 'ba'

and so on (filling in the gaps), optionally starting with the empty string.

Input:

• The amount of consecutive characters the program has to print up to.

Output:

• An array containing each string OR one string per line

Clarifications:

• The order doesn't matter, you can print uppercase or lowercase letters first if you want.

• The output can return any type of enumerable, doesn't have to be an array specifically, although I doubt printing all the combinations won't be the easiest way to go.

• An input of 3 would print all the string from 'a' (or '') to '999'‚ an input of 5 up to '99999' and so on.

Answer 1

Jelly, 7 bytes

ØWṖṗR;/

This is a monadic link that accepts an integer as input and returns an array of strings.

Try it online!

How it works

ØWṖṗR;/  Main link. Argument: n

ØW       Yield 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789_'.
  Ṗ      Remove the last element (underscore).
    R    Range; yield [1, ..., n].
   ṗ     Cartesian product. For each k in the range, this yields the arrays of all
         strings of alphanumeric characters.
     ;/  Concatenate the arrays of strings of each length.

Answer 2

Haskell, 65 bytes

a#b=[a..b]
k n=mapM id.('a'#'z'++'A'#'Z'++'0'#'9'<$)=<<(1#)<$>1#n

Usage example: k 3 -> ["a","b","c",....,"997","998","999"].

How it works

a#b = [a..b]        -- helper function that builds a list from a to b


        (1#n)<$>    -- map the function (1#), i.e. "build the list from 1 up to" 
                1#n -- on the list from 1 to n

                    -- now we have [[1],[1,2],[1,2,3]]

              =<<   -- map over this list (and combine results in a single list)
  (        <$)      -- a function that makes length of input copies of
 'a'#'z'++ ... '9'  -- all characters we need

                    -- now we have [["a..9"],["a..9","a..9"],["a..9","a..9","a..9"]]

mapM id.            -- and make the cartesian product of each sublist 

Answer 3

JavaScript (Firefox 30-57), 108 bytes

f=n=>n?[for(s of['',...f(n-1)])for(c of(t='abcdefghijklmnopqrstuvwxyz')+t.toUpperCase()+'0123456789')s+c]:[]

Saved 3 bytes by using toUpperCase. Computing the 62 characters takes me an extra 10 bytes.

Answer 4

Python, 86 bytes

f=lambda n:n*[1]and[x+chr(y)for x in['']+f(n-1)for y in range(128)if chr(y).isalnum()]

Outputs a list of non-empty strings. Recursively prepends each alphanumeric character to each output for n-1 and empty string.

Answer 5

05AB1E, 9 8 bytes

Code:

ƒžj¨Nã€,

Explanation:

ƒ          # For N in range(0, input + 1), do:
 žj        #   Push predefined literal [a-zA-Z0-9_]
   ¨       #   Remove the last character (the underscore)
    N      #   Push N
     ã     #   Take the Cartesian product, with N repetitions.
      €,   #   For each element in the array, print with a newline

Uses CP-1252 encoding. Try it online!.

Answer 6

Cinnamon Gum, 15 bytes

0000000: 689b b718 05be a345 9c4b c283 d077 de    h......E.K...w.

Not short enough, despite this being the exact kind of challenge Cinnamon Gum was made for :(

Compressed by converting from bijective base 96 to base 256. Try it online. Inputs greater than 2 will cause problems on TIO.

Explanation

This decompresses to the regex [a-zA-Z0-9]{1,%s}. The h mode then substitutes the input in to %s and outputs all strings matching the regex.

Answer 7

Python 2.7, 136 134 bytes

Thanks to Maltysen and NonlinearFruit for saving 2 bytes

from itertools import*;from string import*;f=lambda n:[''.join(a) for i in range(1,n+1) for a in product(ascii_letters+digits,repeat=i)]

Takes ascii_letters and digits from the string module and uses the Cartesian Product as product from itertools to compute all the combinations.

Output

out = f(3)

print out[:10]
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j']

print out[100:110]
['aM', 'aN', 'aO', 'aP', 'aQ', 'aR', 'aS', 'aT', 'aU', 'aV']

print out[-10:]
['990', '991', '992', '993', '994', '995', '996', '997', '998', '999']

Answer 8

Ruby, 82 bytes

Constructs cartesian products of the character set up to the given length. The character set is generated by grabbing all characters between 0 and z and filtering out non-word characters and also _.

->n{a=(?0..?z).grep(/\w/)-[?_];r=[]
n.times{|i|r+=a.product(*[a]*i).map &:join};r}

Answer 9

Pyth - 13 12 bytes

1 bytes saved thanks to @Jakube.

sm^s+rBG1UTh

Try it online here.

s                    Add up the lists of different lengths  
 m          (Q)      Map implicitly over input
  ^     h(d)         Cartesian product of string to implicit lambda var + 1
   s                 Add up list
    ++               Concat up three things
     G               Alphabet
     rG1             Uppercase alphabet
     UT              All digits

Answer 10

Python 2, 106 97 bytes

from string import*
f=lambda n,r=['']:n and r+f(n-1,[x+y for x in r for y in letters+digits])or r

Try it on Ideone.

Answer 11

MATL, 12 bytes

:"3Y24Y2h@Z^

This takes a number as input.

Try it online!

Explanation

:       % Implicitly take input, say N. Generate range [1 2... N]
"       % For each number in that range
  3Y2   %   Predefined literal: string with all letters, uppercase and lowercase
  4Y2   %   Predefined literal: string with all digits
  h     %   Concatenate horizontally
  @     %   Push number of characters corresponding to current iteration
  Z^    %   Cartesian power. Each result is a row 
        % End for each. Implicitly display

Answer 12

, 21 chars / 27 bytes

ⒶïⓜᵖɱĬ⟦ᶛ+ᶐ+⩤9⨝],⧺_)ė)

Try it here (Firefox only).

Nope. Nope. Nope.

Explanation

ⒶïⓜᵖɱĬ⟦ᶛ+ᶐ+⩤9⨝],⧺_)ė) // implicit: 
Ⓐïⓜ                    // [...Array(input)].map(($,_)=>...)
    ᵖ                   // push to stack:
     ɱĬ⟦ᶛ+ᶐ+⩤9⨝],⧺_)   // list of n-digit numbers in [a-zA-Z0-9]-ary
                     ė) // formatted into a matrix (no spaces)
                        // implicit stack output, newline-separated

Answer 13

Perl, 113 bytes + whitespace

@r="";
for (1..shift) {
  @r = sub {
    map { $c=$_; map $c.$_, @{$_[1]} } @{$_[0]}
  }->(\@r, [0..9, "a".."z", "A".."Z"])
}
map say($_), @r

Use "perl -E" on the above, with an argument that's a number. I could probably decently have not counted the last "map say" in the chars count.

Answer 14

APL, 38 37 bytes

{⊃{⍵,,⍺∘.,⍵}/⍵⍴⊂,¨⎕a,⎕d,⍨⎕ucs 96+⍳26}

Answer 15

J, 50 bytes

62&(('0123456789',~(,toupper)u:97+i.26){~#~#:i.@^)

Half of the bytes, 25 to be exact, are spent generating the letters and digits needed.

Answer 16

R, 73 bytes

y='';x=c(letters,LETTERS,0:9);for(i in 1:scan())cat(y<-outer(y,x,paste0))

y starts off as empty string, x as the base case 'a','b','c',...,'8','9'. outer takes each of its input arguments, and applies the function paste0 to each combination of elements in y and x which concatenates the strings. y saves the result, cat prints it, and it iterates through STDIN number of times of doing this.

Try it online!

Answer 17

Jq 1.5, 97 bytes

range(.)as$n|[[range(97;123),range(65;91),range(48;58)]|implode/""|combinations($n+1)]|map(add)[]

Expanded

  range(.) as $n           # for each n-digit sequence
| [
      [                    # build array of ordinals for
        range(97;123),     #   a-z
        range(65;91),      #   A-Z
        range(48;58)       #   0-9
      ]
    | implode/""           # make into array of strings
    | combinations($n+1)   # generate array of n-element combinations
  ]
| map(add)[]               # convert to sequence of strings

Try it online!

Answer 18

Bash + GNU utilities, 90

printf -vs %$1s
eval printf '%s\\n' ${s// /{=,{a..z\},{A..Z\},{0..9\}\}}|sed s/^=*//\;/=/d

Input as a command-line parameter. Output is a whitespace-separated list.

Works for inputs upt and including 3. Run out of memory with 4 - the eval printf takes an the entire set of 63ⁿ elements of the bash expansion.

Answer 19

Bash + GNU utils, 66

Different (and I think slightly novel) approach to my other answer:

dc -e"64 $1^[d2 48^r-P1-d0<m]dsmx"|base64 -w8|sed s_^/*__\;/[+/]/d

• dc counts down from 2⁴⁸-1 to 2⁴⁸-64ⁿ and Prints each resulting number as a bytestream (i.e. base 256). If the input is between 1 and 4 inclusive, this is guaranteed to be exactly 6 bytes per number.
• base64 converts this to base64 output and thus 8 bytes per base64 digit, one per line.
• sed strips off leading / (base64 digit 63), and then removes any lines containing + or / (base64 digits 62 and 63). This leaves the required sequence.