Print X without X (robber's thread)

Question

This is the robber's thread of a cops-and-robbers challenge. You can view the cop'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 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 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 be select cop answers and write programs in language Y which take no input and output X. They will post these "cracks" as answers in this thread. A crack need only work not 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

Robbers will be scored by the total number of successful cracks with more cracks being better.

Answer 1

Keg, cracks Lyxal's answer

aA%,aA%,KA%,aA%,nA%,aA%,lA%,aA%,oA%,aA%,yA%,aA%,7,aA%,bA%,aA%,Àa%,aA%,673**,aA%,é85**,aA%,¾b%,aA%,fA%,KA%,aA%,aA%,KA%,aA%,nA%,aA%,lA%,aA%,oA%,aA%,yA%,aA%,7,aA%,bA%,aA%,Àa%,aA%,673**,aA%,é85**,aA%,¾b%,aA%,fA%,KA%,

Ungolfed to avoid what appears to be a bug in Keg. I can't remember if this is exactly what I had in mind a month ago as I can't find the file and never bothered to generate a TIO link in my history, but I reckon it's pretty close.

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Explanation:

While taking away + and - will make it a little harder to generate numbers, % is still a powerful tool. Unsurprisingly, it's a modulo operator, and by moduloing, say, 65 and 97 (characters A and a, respectively), we can get 32, corresponding to space. It's just subtraction with more steps! We mostly just abuse this to get the characters we need, occasionally switching our base to something like a. This won't work for characters greater than 125 (I mean, it could, but I don't want to look up UTF-8 codes), however, and we need two of these: ~ and ⑨. For ~ we just multiply 6, 7, and 3 to get 126. ⑨ has a prime factorization of 2^3 * 5 * 233, so we use é (char code 233), 8, and 5 and multiply through.

Answer 2

AlphaBeta, 228 bytes, cracks @PkmnQ's answer

wEFrErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErErLErLErLErLErLErLErLErLErLErLErLErL

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w        # set Register 3 value to 1 (Register 1 to the power of Register 2; both initially 0)
EF       # copy Register 3 value to Registers 1 and 2
r        # set Register 3 value to 2 (sum of values of Registers 1 and 2)
Er × 94  # 94 times, increment Registers 1 and 3
ErL × 12 # 12 times, increment Registers 1 and 3 and print Register 3 as char

Answer 3

Lua, 2433 bytes, cracks @LuaNoob's second answer

io.write(_G[([[string]])][string.lower([[CHAR]])](string.len([[................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[..................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[...................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[....................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.....................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[......................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.......................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[........................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.........................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[..................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[...................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[....................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[......................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.......................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[..........................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[...........................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.............................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[...............................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[............................................................................................]])).._G[([[string]])][string.lower([[CHAR]])](string.len([[.................................................................................................]])))

Try it online! Untested in 5.1 (TIO has 5.3.5), but I don't believe there's any code here that depends on the minor version.

Pretty similar to the first crack. This time we don't have a or #, which we work around by calling string.char as _G[([[string]])][string.lower([[CHAR]])] and # as string.len. I used this Ruby code to generate the Lua:

X = %q(0123456789 "#$&'*+-/\\a)
luaify = ->(s) { s.bytes.map{|b|"_G[([[string]])][string.lower([[CHAR]])](string.len([[#{'.'*b}]]))"}*'..' }
print "io.write(#{luaify[X]})"

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Answer 4

Forth (gforth), 13 bytes, cracks binarycat's challenge

.\"0x0B\x20\t\n"

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This also happens to be my first Forth program. 😃

Explanation

It is really simple. I use .\" which allows me to use C-style escapes, and then I use a vertical tab (0x0B) to delimit the tokens, as Gforth uses the same whitespace rules as isspace(). The rest is just writing everything in C escapes.

Answer 5

Rattle, 48 bytes, cracks @DanielH.'s answer

+4*4*7,%=+4*7+7+7+++,+7+7,%=+7+7++b*7b**7b*b*7bB

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Pretty straightforward: push a bunch of values to the stack, then either print them as characters (,) or concatenate them to the print buffer (b) as floats. I use %= (modulo with top of stack) to reset the stack.

Answer 6

Dis, 47 bytes, cracks @tailsparkrabbitear's answer

*|||_________________________________________>!

Try it online! Link compiles and runs a copy of Ben Olmstead's interpreter in C.

Explanation

We make use of self-modifying code to execute the banned print instruction.

*|||                                         >  # set the accumulator to 123; also store 123 in cell 45
    _________________________________________   # no-ops
                                             >  # execute cell 45 (modified to codepoint 123), i.e. print accumulator as ASCII character
                                              ! # terminate

Answer 7

Javastack, cracks AUsername's sixth answer

((alphabet length not not) * 1234567890) (add * 1234567889) quote add alphabet alphabet length not not double index add alphabet (alphabet length not not * 17) (add * 16) index add alphabet (alphabet length not not * 18) (add * 17) index add 

Yeah this was way easier than last year's round 6. All I had to do was just change the answer to round 5. ;P

Answer 8

Javastack, cracks Enamresu A's twelfth answer

"abcegiln" "a" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop pop pop swap pop swap pop swap pop swap pop replace "b" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop pop pop pop pop pop pop replace "c" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop pop pop pop pop swap pop swap pop replace "e" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop pop swap pop swap pop swap pop swap pop swap pop replace "g" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop swap pop swap pop swap pop swap pop swap pop swap pop replace "i" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop pop pop pop swap pop swap pop swap pop replace "l" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate swap pop swap pop swap pop swap pop swap pop swap pop swap pop replace "n" ascii "0" "" replace "1" "" replace "2" "" replace "3" "" replace "4" "" replace "5" "" replace "6" "" replace "7" "" replace "8" "" replace "9" "" replace "a" "" replace "b" "" replace "c" "" replace "e" "" replace "g" "" replace "i" "" replace "l" "" replace "n" "" replace "o" "" replace "p" "" replace "q" "" replace "r" "" replace "s" "" replace "t" "" replace "w" "" replace "x" "" replace "y" "" replace "z" "" replace "A" "" replace "B" "" replace "C" "" replace "D" "" replace "E" "" replace "F" "" replace "G" "" replace "H" "" replace "I" "" replace "J" "" replace "K" "" replace "L" "" replace "M" "" replace "N" "" replace "O" "" replace "P" "" replace "Q" "" replace "R" "" replace "S" "" replace "T" "" replace "U" "" replace "V" "" replace "W" "" replace "X" "" replace "Y" "" replace "Z" "" replace "!" "" replace "~" "" replace " " "" replace "#" "" replace "&" "" replace "%" "" replace "'" "" replace "/" "" replace ":" "" replace "@" "" replace iterate pop pop pop pair pair pair pair pair pair pair swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop swap pop iterate iterate iterate iterate iterate iterate iterate pop pop pop pop pop pop swap pop replace

... 10526 bytes. This one was suffering.

Answer 9

Javastack, cracks Enamresu A eighth answer

zpake zpake equal "" add "" ceil index  
zpake zpake equal "" add (1) index add
(111) zpake zpake equal "" add (1) index "cha" add eval add
(115) zpake zpake equal "" add (1) index "cha" add eval add
(98) zpake zpake equal "" add (1) index "cha" add eval add
(103) zpake zpake equal "" add (1) index "cha" add eval add
(1234567890) add

For clarity:

zpake ceil zpake ceil equal = 1
(zpake ceil zpake ceil equal * n)(add * n - 1) = n

JavaScript abuse ftw

Answer 10

Javastack, cracks Enamresu A's seventh (yes, seventh) answer

((alphabet length alphabet length divide) * 1234567890) (add * 1234567889)
alphabet (4) index alphabet (19) index add alphabet (14) index add alphabet (20) index add alphabet (16) index add eval add
alphabet (2) index add
alphabet (position of r in the alphabet) index add
alphabet (position of s in the alphabet) index add
alphabet (position of y in the alphabet) index add
alphabet (position of o in the alphabet) index add

Replace numbers in brackets ((n)) with (alphabet length alphabet length divide) * n (add * n - 1)

Do you see how I put seventh in italics? That's an ode to the fact that this isn't my first time reaching round 7 of a match.

Answer 11

Javastack, cracks Enamresu A's fifth answer

((maybe length not) * 1234567890) (add * 1234567889) quote add alphabet maybe length not double index add alphabet (maybe length not * 17) (add * 16) index add alphabet (maybe length not * 18) (add * 17) index add 

Traditionally, the next round is the one where I actually have to think for a while. Here's hoping I don't.

Answer 12

Javastack, cracks Enamresu A's fourth answer

not times context (increment * 1234567890) context (increment * 34) char context (increment * ascii value of "q") pair context (increment * ascii value of "d") join context (increment * ascii value of "l") pair context (increment * ascii value of "w") join pair sum

Vyxal features ftw.

That's enough for today.

Answer 13

Javastack, cracks Enamresu A's third answer

not increment * 1234567889 flatprint not increment * (ascii value of " - 1) char flatprint not increment * (ascii value of d - 1) flatprint not increment * (ascii value of w - 1) flatprint not increment * (ascii value of q - 1) flatprint

H...hey actually give me time to actually write a post please!

Answer 14

Javastack, cracks AUsername's thirteenth answer

107 char 100 char 115 char 109 char 117 char 106 char 118 char 102 char 98 char wrap 1 repeat "," "" replace

Sussy baka

Answer 15

Vyxal O, 707126 bytes, cracks EmanresuA's seventh (yes, seventh) answer

Sample:

⟨\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o|\o⟩LkA≬\D<ṡ∷∷Ė

Full code

Answer 16

Vyxal O, 299195 bytes, cracks EmanresuA's eigth answer

Sample:

×ǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏǏLkA√y$_y_y_y_Ė

Full code

...

Answer 17

Vyxal O, 801294 bytes, cracks EmanresuA's ninth answer

Sample:

¶ḃʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLʀLkA‛ABo↓ǐĖ

Full code (ignore the file name it's a very unfunny joke)

Yes.

Answer 18

Vyxal, 1606416 bytes, cracks lyxal's answer

Sample:

εuεuεuεuuεuεuεuεuε\‛§εḭĖuuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuεuuεuεuεuεuε\‛§εḭĖĖuuε

Full code

Generator program

Answer 19

!@#$%^&*()_+, 141 bytes, cracks @null's answer

**********************************************************************************************_@*******************************************_@

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The strategy to print a character is simple:

1. Find the character's codepoint and execute that many copies of the * command. Each * attempts to read a byte of input from STDIN, but when the input is empty \$-1\$ is added to the top of the stack instead.
2. Negate the top of stack (_).
3. Pop and print the top of stack as a character (@).

(Using loops might be shorter, but this isn't code golf.)

Answer 20

Brainf**k - 98 Bytes CreaZyp154's Answer

++++++++++++++++++++++++++++++++++++++++++++.+.+++++++++++++++.++.+++++++++++++++++++++++++++++.++

Output

,-<>[]

Answer 21

Brainfuck, cracks CreaZyp154's answer

++++++++++++++++++++++++++++++++++++++++++++.+.+++++++++++++++.++.+++++++++++++++++++++++++++++.++.

Attempt This Online!

Answer 22

APL (Dyalog Unicode), 81 bytes, cracks Ada's answer

∆←⍎'⎕A',22⊃⎕A
⎕←(25↑66↓∆),(26↑17↓∆),(97⊃∆),⍕2+1

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This was pretty easy. ⎕A is our escape hatch - it's the list of all 26 capital letters in the English alplhabet. We want ⎕AV, a string containing all the letters Unicode APL uses. 22⊃⎕A gets the 22nd element of ⎕A ("V"), and we append that to the string '⎕A' and execute it to get the value of ⎕AV. That is assigned to a variable ∆.