The Challenge

Create a program or function that takes no input, and outputs (or returns):

I'm a programming paradox — no I'm not.

Without using a character twice in any string, or digit twice in any integer.


  1. You may not use any character twice within a string. For example, the word "test" would violate this rule.

  2. You may not use any character twice between strings. For example, if somewhere in your code you have the string "hi", no other strings may contain the substring "h" or "i".

  3. You may not use a digits more than once within an integer. For example, the integer 200 would not be acceptable.

  4. You may not use a digit more than once between integers. For example, if you have the integer 40 in your code, you may not have the integer 304.

  5. The above rules do not apply between data types. You could, for example, have the string "9" and the integer 9 in your code.

  6. An uppercase letter is considered a separate character from the lowercase.

  7. You may only use printable ASCII characters in your strings.

  8. You may not set variables to each character and add them together.


Here is an example, written in Python 2, of what the same challenge might look like with the string "Hello, World!" instead.

print"He"+"l"*2+"o, "+"W"+chr(int("1"*3))+"r"+chr(108)+"d!"

Note: For those wondering why I chose this particular string; I chose it because it has several repeated characters and a repeated word. It has no greater significance or meaning.

  • \$\begingroup\$ Does the repeated rule only apply to strings, and not the rest of the code? \$\endgroup\$ Sep 24, 2015 at 15:54
  • 17
    \$\begingroup\$ I don't like that you added a rule to rule out a posted answer. It's not fair to ETHproductions that they figured out a solution but don't get to use it because you don't like it. Also, I don't think saving chars to variables is any more cheap than using character codes as in your example. \$\endgroup\$
    – xnor
    Sep 24, 2015 at 17:11
  • 18
    \$\begingroup\$ -1 for changing the rules. \$\endgroup\$
    – Dennis
    Sep 24, 2015 at 18:10
  • 9
    \$\begingroup\$ The dash in the text "I'm a programming paradox — no I'm not." you posted is not ASCII 39 "-" \$\endgroup\$
    – Max
    Sep 24, 2015 at 18:27
  • 9
    \$\begingroup\$ It's not clear to me whether when you say string you mean string literal, and similarly for integer vs integer literal. \$\endgroup\$ Sep 24, 2015 at 18:33

5 Answers 5


Python 2, 186 155 139 138 126 109 98 bytes

I don't know if this is a loophole...

print list(locals())[3].translate("adgimnoprtx' -.I"*16)

don't think I can golf more than this...

  • \$\begingroup\$ Very nicely done! \$\endgroup\$ Sep 24, 2015 at 17:42
  • 1
    \$\begingroup\$ This seems to use 3 twice in integers 35 and 39. You could always use 42-7 for 35 or something similar though. \$\endgroup\$
    – Geobits
    Sep 24, 2015 at 17:43
  • 3
    \$\begingroup\$ chr(39) can be replaced with "'" and chr(35) with "#". Saves you bytes and puts you in the rules. Also, you can do r=replace and save a ton of bytes. You're also calling list twice. \$\endgroup\$ Sep 24, 2015 at 17:45
  • 1
    \$\begingroup\$ @MorganThrapp you have to call r like this: r("My String", "My", "A") which returns "A String". \$\endgroup\$ Sep 24, 2015 at 18:08
  • 1
    \$\begingroup\$ @FryAmTheEggman Right, duh, I forget when you call it as a class method you have to pass in the instance. @Max I0m_a_programming_paradox_3_no_I0m_not1="#";r=str.replace print r(r(r(r(list(locals().iteritems())[4][-2],'0',chr(39)),"_"," "),"1","."),"3","-") saves you 10 bytes. \$\endgroup\$ Sep 24, 2015 at 18:11

C++14, 327 bytes

#include <iostream>
#define x(y) <<(y)[s]
std::string s[]={"I'"," ","a","p","r","o","g","m","n","i","d","x","—","t","."};enum{J,S,A,P,R,O,G,M,N,I,D,X,W,T,Z};[]{std::cout x(J)x(M)x(S)x(A)x(S)x(P)x(R)x(O)x(G)x(R)x(A)x(M)x(M)x(I)x(N)x(G)x(S)x(P)x(A)x(R)x(A)x(D)x(O)x(X)x(S)x(W)x(S)x(N)x(O)x(S)x(J)x(M)x(S)x(N)x(O)x(T)x(Z);}();

I'm defining a macro which returns a string to the << operator, mapping the necessary characters in a string array and access them with an enum

  • \$\begingroup\$ I don't think I can golf this particular solution any more, but tips are always welcome! \$\endgroup\$ Sep 24, 2015 at 17:26

Javascript (ES6), 142 105 98 96 bytes

[a="I'm","a",`${y=>programming}`.slice(3),`${no=>paradox}`.slice(4),'-',x="no",a,x+"t."].join` `

Another possible rule-breaker, but it was fun, anyway. :)

Original version:

[a="I'm",(''+(b=>a)).substr(3),(''+(is=>programming)).substr(4),(''+(Fermi=>paradox)).substr(7),'-',(''+(yes=>no)).substr(5),a,'not.'].join` `
  • \$\begingroup\$ I don't know ES6 but.... googling i found thath is=>programming is like: function f(is){return programming} right? I don't understand why this should return the string "programming"? \$\endgroup\$
    – Max
    Sep 24, 2015 at 20:22
  • \$\begingroup\$ @Max Yes, you are correct about the fat arrow function declaration. ...`${y=>programming}`... is the same as ...(''+(y=>programming))..., (or ...(''+(function(y){return programming;}))...) which returns "y=>programming", and a substring is taken off of that. Not sure if this is allowed or not. \$\endgroup\$ Sep 24, 2015 at 20:24
  • \$\begingroup\$ does the string concatenation "generate" automagically a string representation of the function? \$\endgroup\$
    – Max
    Sep 24, 2015 at 20:28
  • 1
    \$\begingroup\$ @Max Yep. Javascript's type conversion can be ridiculous sometimes. \$\endgroup\$ Sep 24, 2015 at 20:31

Javascript (ES6), 89 86 84 Bytes

`${y=>I0m3a3programming3paradox313no3I0m3not2}`.slice(3).replace(/\d/g,m=>"'—. "[m])

Haskell, 320 bytes

import Data.Char

data Letter = A|D|I|I'm|MM|P|R|G|N|O|X|Y|S|T deriving Show

transform :: Letter -> String
transform S = " "
transform Y = "—"
transform I'm = "I'm"
transform x = map toLower $ show x

main :: IO ()
main = print $ transform =<<
  • \$\begingroup\$ What language is this? \$\endgroup\$
    – Zach Gates
    Sep 24, 2015 at 18:00
  • 2
    \$\begingroup\$ This is Haskell I believe. \$\endgroup\$ Sep 24, 2015 at 18:00

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