String permutations

Question

Print the biggest-size subset of strings in the input that are all permutations of each other. If there are ties, any one will do. If no strings are permutations of each other (for example, only one string was given or the strings contain distinct characters), this is just one of the strings. If no strings were passed in , do not output anything or output an empty list.

Test cases:

Input => Output
["ABCDE", "EDBCA", "XYZ", "ZYX", "ZXY"] => ["XYZ", "ZYX", "ZXY"]
["A"] => ["A"]

• 640KB: Is that an example of just input or are the outputs also in that same line? Can you include clear examples of expected output, with at least two test cases?
• manatwork: To make this a challenge suitable for CGCC is not enough to just translate the old Russian SO question.
• wastl: This needs an objective winning criterion, such as "smallest number of bytes wins"
• Grimmy: @close voters: please don’t close code-golf questions for not having an objective primary winning criterion. If it’s code-golf, the winning criterion is "fewest bytes of source code wins".
• Mitchell Spector: I've voted to reopen, presuming that the only problem was that the winning criterion was inadvertently omitted -- although it's clear because of the code-golf tag. (If there's some other issue, please post it, of course.)

Answer 1

05AB1E, 6 bytes

.¡{}éθ

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.¡ } # group the input strings by:
 { # sort (all permutations of each other will be identical when sorted)
 é # sort the groups by length
 θ # output the last (longest) group

Answer 2

T-SQL, 267 bytes

SQL queries was totally made to solve this type of question

SELECT top 1WITH TIES x FROM(SELECT(SELECT a FROM(SELECT
top 999substring(x,number+1,1)a,*FROM
@,spt_values WHERE type='P'and number<len(x)ORDER BY a)c
WHERE x=t.x for xml path(''),type).value('.','char(9)')v,x FROM @ t)z 
ORDER BY-count(*)over(PARTITION BY v),-len(x)

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• Realitätsverlust: What the fuck I'm actually intimidated now

Answer 3

Japt -h, (削除) 6 (削除ここまで) 5 bytes

üñ ñl

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üñ ñl :Implicit input of array
ü :Sort & group by
 ñ : Sorted strings
 ñ :Sort by
 l : Length
 :Implicit output of last element

Answer 4

Perl 6, 36 bytes

{max .classify(~*.comb.sort){*}||''}

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Output an empty string for an empty input. If we could output something else, for example -Inf, then this could be:

Perl 6, 31 bytes

*.classify(~*.comb.sort){*}.max

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Answer 5

J, 19 bytes

0({>\:#&>)/:~&></.]

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-2 bytes thanks to FrownyFrog

Similar approach to Grimmy's answer.

• FrownyFrog: Bring { into the () and you don't need [:
• Jonah: Very nice, thank you @FrownyFrog

Answer 6

Python 2, (削除) 79 (削除ここまで) 77 bytes

lambda A,S=sorted:A and max([[y for y in A if S(x)==S(y)]for x in A],key=len)

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2 bytes thx to wilkben.

The A and... is only required to deal with the empty input.

• wilkben: 77 bytes

Answer 7

Clojure, 54 bytes

#(some val(sort-by(comp count val)>(group-by sort %)))

Returns nil for empty input.

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