Anadromes

An anadrome is similar to a palindrome except, rather than spelling the same word or phrase when reversed, it spells a different word or phrase. An anadrome is a special case of an anagram.

Anadrome is a portmanteau of the words anagram and palindrome.

For instance, regal and lager are anadromes.

Task

Using the words.txt file from https://github.com/dwyl/english-words, find and display all of the anadrome pairs with more than 6 characters.

Each word pair should only show up one time in the list.

Alternate download location.

Factor

Works with: Factor version 0.99 2022-04-03

<lang factor>USING: assocs grouping hash-sets io.encodings.ascii io.files kernel math prettyprint sequences sets sets.extras ;

"words.txt" ascii file-lines [ length 6 > ] filter dup >hash-set '[ reverse _ in? ] filter [ reverse ] zip-with [ all-equal? ] reject [ fast-set ] unique-by .</lang>

Output:

{
    { "amaroid" "diorama" }
    { "degener" "reneged" }
    { "deifier" "reified" }
    { "deliver" "reviled" }
    { "dessert" "tressed" }
    { "desserts" "stressed" }
    { "deviler" "relived" }
    { "dioramas" "samaroid" }
    { "gateman" "nametag" }
    { "leveler" "relevel" }
    { "pat-pat" "tap-tap" }
    { "redrawer" "rewarder" }
    { "reknits" "stinker" }
    { "relever" "reveler" }
    { "reliver" "reviler" }
    { "revotes" "setover" }
    { "sallets" "stellas" }
}

Raku

<lang perl6>my @words = 'words.txt'.IO.slurp.words.grep: *.chars > 6;

my %words = @words.pairs.invert;

put join "\n", @words.map: { %words{$_}:delete and sprintf "%10s ↔ %s", $_, .flip if ($_ ne .flip) && %words{.flip} }</lang>

Output:

   amaroid ↔ diorama
   degener ↔ reneged
   deifier ↔ reified
   deliver ↔ reviled
   dessert ↔ tressed
  desserts ↔ stressed
   deviler ↔ relived
  dioramas ↔ samaroid
   gateman ↔ nametag
   leveler ↔ relevel
   pat-pat ↔ tap-tap
  redrawer ↔ rewarder
   reknits ↔ stinker
   relever ↔ reveler
   reliver ↔ reviler
   revotes ↔ setover
   sallets ↔ stellas