Convert string to number

Question

Task

The task is to convert a string to a number. It must accept the string via stdin and output the number via stdout.

You convert a string to a number by replacing each letter of the string by its index (mind that you don't need to replace it with the index, that's just an example. You are allowed to replace it with anything you like, as long as the output is decodable) in the following list (you don't need to convert any other characters):

Characters: abcdefghijklmnopqrstuvwxyz1234567890 (the input will only either be lowercase letters, or/and a number).

Additionally, you must make the output decodable, so if you have output 0 for input a, and somebody inputs bl, then the output will be something like 111. This is not decodable since the program might interpret it as bbb or lb or bl. You might make it decodable by making sure the the number that each character outputs always has a length of 2. Any other way of making sure your output is decodable is allowed, but you must explain how one would decode the output in your answer.

Standard loopholes are not allowed. This is code golf, so shortest code wins!

EDIT: By decodable, just to clarify, I mean that you can convert the output back into the input. Your program doesn't need to feature decoding features, only encoding.

Examples

Input    Output
a        00
ab       0001
1        26

Answer 1

Pyth, 1 byte

C

Try it here!

Converts a string to a number

Decode with the following Python code:

def decode(x):
    rest, char = divmod(x, 256)
    if rest < 256: return chr(rest)+chr(char)
    return decode(rest)+chr(char)

Answer 2

C 69 61 52 62 Bytes

i;char v[99];main(){gets(v);while(v[i])printf("%.3d",v[i++]);}

Now taking input from stdin, each character code is 3 digits.

a.exe thisisatest

116104105115105115097116101115116

Answer 3

Ruby, 97 37 44 bytes

lambda{|s|s.chars.map{|c|c.upcase.ord}.join}

Take the ordinal of each character in s converted to uppercase (to ensure 2 chars per number for ordinals)

Answer 4

PowerShell v2+, 42 32 bytes

-join([char[]]$args[0]|%{$_-38})

Takes input $args[0], treats it as a char-array, sends it into a loop, and each loop cast the char as an int (implicit) minus 38. Those are all encapsulated in parens and -joined into one string. That string is left on the pipeline and printing is implicit.

The lowest ASCII point of abcdefghijklmnopqrstuvwxyz0123456789 is 0, with 48. The highest is z with 122. By subtracting 38 from each code point, we're guaranteed distinct two-digit number for each input character.

Examples

PS C:\Tools\Scripts\golfing> .\convert-string-to-number.ps1 'ab'
5960

PS C:\Tools\Scripts\golfing> .\convert-string-to-number.ps1 'ppcg'
74746165

PS C:\Tools\Scripts\golfing> .\convert-string-to-number.ps1 'error404'
6376767376141014

PS C:\Tools\Scripts\golfing> .\convert-string-to-number.ps1 'abcdefghijklmnopqrstuvwxyz0123456789'
596061626364656667686970717273747576777879808182838410111213141516171819

Answer 5

Bash + coreutils, 20

od -vbAn|tr -d ' \n'

The index of each character in the ASCII table is given in octal by od, which ensures each octal number for each input character is exactly 3 digits long (padded with leading zeros as necessary). tr removes the whitespace.

Decoding would be performed by grouping output into groups of 3 digits and then conversion from octal back to ASCII.

Answer 6

S.I.L.O.S, 63 60 55 bytes

loadLine
b=256
lbla
c=get b
printIntNoLine c
b+1
if c a

Prints ASCII value.

Try it online!

Answer 7

Python 3, 86 bytes

I appear to have misunderstood what the question allows... Either way, this exactly matches the test cases given.

print(''.join('%02d'%'abcdefghijklmnopqrstuvwxyz0123456789'.index(i)for i in input()))

Ideone it!

Answer 8

GS2, 1 byte

Byte 14, which, in CP437, is ♫.

Try it online!

Decoding is possible: get all matches of the regex (1..|..) and map them from decimal ASCII code points to ASCII characters.