Task 1 (attempt #2)

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+#!/usr/bin/perl
+
+# Perl Weekly Challenge - 118
+# - https://perlweeklychallenge.org/blog/perl-weekly-challenge-118/#TASK1
+#
+# Task 1 - Binary Palindrome
+#
+# Author: Niels 'PerlBoy' van Dijke
+
+use v5.16;
+use strict;
+use warnings;
+
+use Math::BigInt;
+
+use Test::More;
+
+# Prototype(s)
+sub isBinaryPalindrome($);
+
+my %tests = (
+  5 => 1,
+  4 => 0,
+  9 => 1,
+  92 => 0,
+  # Now some real challenges:
+  '87654321000012345678' => 0,
+  '77194726158210796949047323339125271902066562321453396538483931136131497022805' => 1,
+  '9096277536784585483240416959567103451191883478284251193514416195152412459618527660091914322009559535522570905762842795912065673925408126515314057188586933' => 1,
+  '390520815125593832371201697557683624491649534912901063643439413447139822863062906277079006273425577853445715844801588127146480334303438634964256432990176608224878768486258600947343601637695607728348109788264339635836155197549535941692743300329974746863355305611317558289413771864738304339390446884778588808422645889858617862446537780027060422416346663958099847404236107613580798319044445091549200574727166165228621771181084035836181195365834105668617904174505103477930561669709938616552640420092052483600909110756129217312104708327535891661407921594300013183081491389611184433598547514094574949978459326057992386614899828467492613606747654322873143331601686076385652190953089604400472524840507492345956054437362719341542264830374240351214439821838436994367564099748207975' => 1,
+  '30420870501830658244148948732224404217342708033527580850831453232482181974424130263498721816183762713186497654433463101910432392302669795264593430452308705577792439180820164559840712624581697015256080328595081563691884887966022352598882122446213882099281149316168476669542316213722373693620829396128713734980773976974780869098575147279674021211113701671985932165689256627405162912403495055711286767619699102675978272511992832575030990198128609741644635772467941438682368246680914255854766493352308874864233727671409360525102696547280664474358892673919573186256762944290413735188055534315001317678929934077126393950847593950707407597087760686781836671147599520769256723053565731764486148196331601402102994940008093436478378805531201716187295264427922839406420155164083625103641845966094705857884998581973686233845853892253944014152628584058328694791102891690448048438091485903100668725541560014886082050907359188291037811773977401573876011701005604613643633404889391818647294932964017966003081525288752382572500314089057171184548639686361899323807887770533254577435329677589223591692679559260249372091759449793917384279130460488987636758630393185893438906611972048204416758651037784396187329086767968670816979363153092743506130430708990514476677076076379988593166341491306383411909116482005346991092175488409796222756065611971763653644119376384994495350380858876963052860192571384451362017876989943341353274127149466801473037539931725912434119099922995276532144225615942035281332572715510022689749397955371341861066914160368835845080109187964555517587537085073194937627436374786038562561773391814382014839179311823851594182703360755902480395009633743331779731561371551623661080643607686065031005499752336844556402053611296484589931601829085673936805205532631574218322090693883342208418286039836484819416091603596640840198898945225614084025359917071719' => 1,
+);
+
+foreach my $test (keys %tests) {
+  is(isBinaryPalindrome($test),$tests{$test},sprintf("test: %d digits",length($test)));
+}
+
+done_testing;
+
+sub isBinaryPalindrome($){
+  my ($i) = @_;
+
+  # Only binary numbers with their LSB set can be a binary palindrome
+  return 0 if (substr($i,-1) eq '0');
+
+  my $b1 = substr(Math::BigInt->new($i)->as_bin(),2);
+  my $b2 = join '',reverse split //,$b1;
+
+  return ($b1 eq $b2 ? 1 : 0);
+}