ch-1.pl

#!/bin/perl

=pod

The Weekly Challenge - 180
 - https://theweeklychallenge.org/blog/perl-weekly-challenge-180/#TASK1

Author: Niels 'PerlBoy' van Dijke

Task 1: First Unique Character
Submitted by: Mohammad S Anwar

You are given a string, $s.

Write a script to find out the first unique character in the given string and print its index (0-based).

=cut

use v5.16;
use warnings;

# Prototype(s)
sub firstUniqueChar($);

use List::MoreUtils qw(singleton);

use Test::More;
use Test::Deep qw(cmp_deeply);


cmp_deeply(firstUniqueChar('Perl Weekly Challenge'),[0,'P']);
cmp_deeply(firstUniqueChar('Long Live Perl'),[1,'o']);

done_testing();


sub firstUniqueChar($) {
  my $re = sprintf '(?i)(.*?)([%s])', join '',singleton split //,lc $_[0];
  my (@r) = $_[0] =~ m#$re#;

  return [length $r[0], $r[1]];
}