Print X without X (cop's thread)

Question

This is the cop's thread of a cops-and-robbers challenge. You can view the robber's thread here

A pretty common beginner style question is to print some string, but there's a catch! You need to do it without using any of the characters in the string itself!

For this challenge, we will find out who is the best at printing X without X. There are two threads to this, a cop's thread and a robber's thread.

In the cop's thread (this thread), users will choose a language (which we will call Y) and a string (which we will call X) and write a program in language Y which takes no input, and outputs exactly X without using any of the characters in X. The cop will then post both X and Y without revealing the program they have written.

Robbers will select the cop's answers and write programs in language Y which take no input and output X. They will post these "cracks" as answers in their thread. A crack need only work, not to be the intended solution.

Once a cop's answer is one week old, so long as it has not been cracked, the cop may reveal their program and mark it as "safe". Safe answers can no longer be cracked and are eligible for scoring.

Cops will be scored by length of X in characters with smaller scores being better. Only safe answers are eligible for scoring.

Extra Rules

You may be as specific or precise in choosing your language as you wish. For example you may say your language is Python, or Python 3, Python 3.9 (pre-release), or even point to a specific implementation. Robber's solutions need only work in one implementation of the given language. So, for example, if you say Python is your language, a robber's crack is not required to work in all versions of Python, only one.

Since command line flags and repls count as different languages, if your language is one of those then you should indicate that as at least a possible option for the language. For ease of use, I ask that you assume there are no command line flags in cases where command line flags are not mentioned.

You may choose to have your output as an error. If your intended solution does output as an error, you must indicate this in your answer.

Find Uncracked Cops

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Answer 1

Javastack, score 11, round 10, Cracked by exedraj.

dfhklmquvx"

Game on... One more time.

Up-to-date copy of the interpreter

I spent all day working on this, so hopefully it holds up for at least 20 minutes...

Answer 2

Javastack, score 8, round 12, Cracked by exedraj

kdhmujvf

No more alphabetical order for you, sunshine!

Probably the last one, unless an unintended crack is found.

Up-to-date copy of the interpreter, with ES2020 stuff removed

Answer 3

Javastack, score 9, round 13, Cracked by exedraj

kdsmujvfb

No more constants for you (except numbers and strings, so not really, but whatever)

Probably the last one, unless an unintended crack is found.

Up-to-date copy of the interpreter, with ES2020 stuff removed

I admit defeat.

My basic idea for rounds 11-13 was that you could use replace to concatenate two values with something like "string1" "string2" "xy" swap "y" swap replace swap "x" swap replace, replacing the x with string1 and the y with string2.

exedraj managed to get around this in round 11 because I had put the result in alphabetical order, so chars could just be removed from the ascii constant. This was exploited more in round 12, so I created this one and replaced ascii with char. However, this was exploited even easier.

exedraj's trick was to wrap the stack, stringify, and remove commas. I couldn't bypass this because even if I removed w, they could use pair pair pair pair pair etc for effectively the same result, and I needed all the chars in pair.

So, that's it for now.

Answer 4

Vyxal, score 250, cracked properly by Aaroneous

 !"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVXYZ[\]^_`abcdefghijmnopqrtuvwxyz{|}~¡¢£¤¥¦§¨«¬¯°±²µ¶¹»¼½¾×Þßæð÷øĊċėĠġİĿŀŻżƈƒƛǍǎǏǐǑǒǓǔȦȧȮȯɖɽɾʀʁΠβελτḂḃḊḋḞḟḢḣḭṀṁṄṅṖṗṘṙṠṡṪṫẆẇẊẋẎẏ‛„‟†‡•…‹›⁋⁰⁺⁼⁽₀₁₂₄₅₆₇₈₌₍€₴℅⅛←↑→↓↔↲↳↵⇧⇩∆∇∑√∞∧∨∩∪∴∵∷≈≠≤≥≬⊍⋎⋏⌈⌊⌐□⟇⟑⟨⟩꘍ꜝ

Frick you with your bullcrap inf. That stops now. No more inf. (at least, not easily).

Edit: It took us a while, but we finally got there. Aaron got my intended solution 100%.

Answer 5

JavaScript (V8), score 20

[+`'"cv-0123456789*]

Good luck! This could be quite easy or quite hard.

Answer 6

Befunge-98 (FBBI), Score: 2, Cracked

Not too difficult, but I don't think this can be made harder in Befunge.

=,

My solution:

4b*:d0p'<1+1k @

Answer 7

Perl 5 + -p, Score: 30, Cracked

Outputs to STDOUT. Perl has so many ways to generate chars so I've probably missed a few alternative cracks, but here goes...

"'/0123456789<CMFQSV\^cmpqsv|~

Answer 8

Python 2, score 26 Cracked

[2517630984, '\\`"a_put']

The same as the output of this program.

---

This may well get cracked fairly quickly so apologies in advance if I am not around promptly to acknowledge it!

Answer 9

Java, Score: 2 (Cracked)

Output (X):

.

(a dot and a newline)

Never golfed before, but saw this and couldn't resist trying; probably will be cracked within the hour, considering it's not really that complicated. My intended solution output to standard error.

Answer 10

Perl 5, Score: 35, Cracked

"'/0123456789<CMPQSTVY\^`cmpqstvy|~

Foiled in my last attempt I'll try another more restrictive set...

Answer 11

Javascript (Browser), Score: 34. cracked

ABDEFGHIJKLMNOPQRTUVWXYZ1234567890

Shouldn't be too hard compared to the other ones.

Answer 12

Javascript (Browser), Score: 27 Cracked

ABDEFGINOPQTUVYZ234567890tf[

Answer 13

Javascript, score 6, Cracked

(\SuC)

Alright, added 3 more characters. Same concept as before, but harder this time.

My solution:

[]["fill"]["constr"+[[][0]+[]][0][0]+"ctor"]`a${[]["fill"]["constr"+[[][0]+[]][0][0]+"ctor"]`a${"ret"+[[][0]+[]][0][0]+"rn "+[[][0]+[]][0][0]+"nescape"}````console.log%28"%28%5c%5c%53%75%43%29"%29`}```

Answer 14

Java, score 2 Cracked

yC\

This is supposed to be printed to stdout. The y doesn't let you use System.out.println, the \ is so you don't use Unicode escapes, and the C is so you don't use reflection. This isn't super hard - I found it with my first Google search to make an answer to this question.

Answer 15

Ruby, Score: 9, Cracked

.'"?%([:<

My code outputs with no trailing newline and works for Ruby 1.8.7 onwards. By design, string creation is difficult.

Edit: I've posted a new version hardened against the weaknesses found by @DomHastings and @Gilles'SO-stopbeingevil'. Because my code is almost unchanged I'll hold off on revealing it.

Answer 16

Part 2: PicoLisp, score: 18 cracked

Segmentation fault

or (similar):

Segmentation fault (core dumped)

(output to STDERR)

A bit harder than my previous answer. . .

Answer 17

><>, score: 17 - Cracked

0123456789abcdefo

I'm going to ban you from using numbers, too! What can you do now?!

Answer 18

><>, score: 19

0123456789abcdeflol

I could've made it 18 but just for the lols

Answer 19

PHP, Score: 1 Cracked

?

No command line flags were used.

Answer 20

PHP7, score: 15 (Cracked)

funtim(){}_=/\~

Answer 21

Setanta, score 3, cracked by Dingus

Probably an easy one.

N I

Here's my solution:

n:=go_téacs(go_uimh("!"))[0]sp:=go_téacs(gníomh(a){})[1]i:=go_teacs(eas@mata(1000))[0]scríobh(n+sp+i)

Answer 22

AlphaBeta, score: 12, Cracked

abcdefghijkl

I think this will get cracked quick, but I can't come up with anything else for AlphaBeta.

Answer 23

LUA 5.1, Score: 22, Cracked

Output

0123456789 "#$&'*+-/\a

Answer 24

Gforth, 3 bytes

(That's a space, followed by a tab, followed by a newline)

Answer 25

x86 Assembly (gcc, Linux), score: 8, safe

Here is one for you x86 programmers.

Textual assembly, 32-bit x86 Linux.

RrL%ljJ.

Your dilemma:

• You can't use any assembler directives because . is banned.
  • You are stuck in AT&T syntax
  • You can't hand-encode instructions with .byte, .asciz, etc.
• Because you lack %, it is impossible to use anything that refers to registers.
• You have libc, but since you can't use CALL, JMP, Jcc, LOOP or RET, it is impossible to use.
• You can still INT $0x80, but since you can't refer to registers, it is impossible to set up.

If you didn't already hate AT&T syntax, you definitely will now. 😈

The header to define the function is provided for you, as well as a template on TIO.

        # String to print (w/o quotes):
        #    "RrL%ljJ."
        # 32-bit Linux, glhf
        # theb  $est(%syntax),%ever
        .att_syntax prefix
        .globl main
main:

TIO template

I actually wanted this to be cracked so I can post an eviler one, but whatever.

My solution: Try it online!

Answer 26

ARM Assembly (GAS, Linux, no libc), score: 7, safe

Textual assembly, not machine code.

bpsBPS.

This makes it so you can't use bx, bl blx, push, pop, svc, swi, str, stm, syscall, mrs, or any assembler directives. Good luck trying to run a syscall or switch to Thumb. 😈

You can assume your code is placed under this exact header, so don't worry about declaring the function.

        .text
        .arch armv5te
        .arm
        .globl _start
_start:

Should be pretty easy for those who are familiar with ARM's assembler. 🙂

My solution I can't get code blocks to work properly in spoilers, so here's a GitHub gist.

Answer 27

Rattle, Score: 35, Cracked

p
-
;
16.0112.01568.03136.021952.0

Note that there should be a trailing newline (technically it's impossible to do it without the trailing newline).

This should be relatively easy to crack...

As it's been cracked, here's my implementation - feel free to try to solve this a different way and teach yourself the language!

7|s[+]`b*~,b*~*b*b*~b=+++++++++++++++++++++++++++++++++++++++++++++,++++++++++++++,

There is an online interpreter available here - all you need to do is replace what's in the "code" section and hit run (I would recommend minimising the header and footer as well). Do not modify the interpreter code (i.e. don't touch the Python code in the header and footer).

Good luck!

Edit

I'm deciding to give out a small hint - try playing around with functions without arguments! Some functions have default values

Answer 28

Lua 5.1, Score: 35 Cracked

Output

 !"#$&'*+-./:;<=>?@GaLl\`0123456789

Answer 29

Lua 5.1, Score: 50 Cracked

Output

     !"#$%&'*+-./0123456789:;<=>?@G\^`ajklmpqvxyz{|}

Thats a TAB and SPACE at the beginning and a new line at the end. My code to produce that is 19542 bytes long in just 1 line. Thats my last try, cause once you come behind this you can come behind everything in LUA in this Thread.

Have fun :-)

Answer 30

YaBASIC, Score:13 Cracked by Dingus

X: The string to crack:

0
1
2
3
4
5
6
7
8
9
A
a
-

The language may be Basic, but is the solution?

Y: The language - YaBASIC:

print "Can you crack it?"

Try it online!