Challenge 74, task 2

3 files changed, 85 insertions, 0 deletions

diff --git a/challenge-074/lance-wicks/perl/ch-2.pl b/challenge-074/lance-wicks/perl/ch-2.pl
new file mode 100644
index 0000000000..8b1fac125b
--- /dev/null
+++ b/challenge-074/lance-wicks/perl/ch-2.pl
@@ -0,0 +1,14 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+
+use lib './lib';
+use FNR;
+
+my @A = @ARGV;
+my $fnr = FNR->new();
+
+my $output = $fnr->from_string($A[0]);
+
+print $output;
diff --git a/challenge-074/lance-wicks/perl/lib/FNR.pm b/challenge-074/lance-wicks/perl/lib/FNR.pm
new file mode 100644
index 0000000000..d76b60b3f7
--- /dev/null
+++ b/challenge-074/lance-wicks/perl/lib/FNR.pm
@@ -0,0 +1,36 @@
+package FNR;
+
+use strict;
+use warnings;
+
+use List::MoreUtils 'frequency';
+use Moo;
+
+sub from_string {
+    my ( $self, $string ) = @_;
+    my $sequence = '';
+
+    my $end = length $string;
+
+    for my $offset ( 1 .. $end ) {
+        my $chars = substr $string, 0, $offset;
+        $sequence .= $self->_fnr($chars);
+    }
+
+    return $sequence;
+}
+
+sub _fnr {
+    my ( $self, $chars ) = @_;
+    my @characters =  split '', $chars;
+    my %frequencies = frequency( @characters );
+
+    for my $key ( reverse @characters ) {
+        return $key if $frequencies{$key} == 1;
+    }
+
+    return '#';
+}
+
+1;
+
diff --git a/challenge-074/lance-wicks/perl/t/FNR.t b/challenge-074/lance-wicks/perl/t/FNR.t
new file mode 100644
index 0000000000..8bb52b5133
--- /dev/null
+++ b/challenge-074/lance-wicks/perl/t/FNR.t
@@ -0,0 +1,35 @@
+use Test2::V0 -target => 'FNR';
+
+subtest 'from_string()' => sub {
+    subtest 'Example 1' => sub {
+        note "Input: ‘ababc’";
+        note "Output: ‘abb#c’";
+        is $CLASS->from_string('ababc'), 'abb#c',
+            'The first example is correct';
+    };
+
+    subtest 'Example 2' => sub {
+        note "Input: ‘xyzzyx’";
+        note "Output: ‘xyzyx#’";
+
+        is $CLASS->from_string('xyzzyx'), 'xyzyx#',
+            'The second example is correct';
+
+    };
+};
+
+subtest '_fnr()' => sub {
+    my %tests = (
+        'a'     => 'a',
+        'ab'    => 'b',
+        'aba'   => 'b',
+        'abab'  => '#',
+        'ababc' => 'c'
+    );
+
+    while ( my ( $input, $expected ) = each %tests ) {
+        is $CLASS->_fnr($input), $expected, "$input should return $expected";
+    }
+};
+
+done_testing;