Merge pull request #11 from manwar/master

update to week 12

1 files changed, 78 insertions, 0 deletions

diff --git a/challenge-011/athanasius/perl5/ch-2.pl b/challenge-011/athanasius/perl5/ch-2.pl
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+++ b/challenge-011/athanasius/perl5/ch-2.pl
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+#!perl
+
+################################################################################
+=comment
+
+Perl Weekly Challenge 011
+=========================
+
+Challenge #2
+------------
+
+Write a script to create an Indentity Matrix for the given size. For example, if
+the size is 4, then create Identity Matrix 4x4. For more information about
+*Indentity Matrix*, please read the
+[ https://en.wikipedia.org/wiki/Identity_matrix |wiki] page.
+
+=cut
+################################################################################
+
+#--------------------------------------#
+# Copyright © 2019 Perlmonk Athanasius #
+#--------------------------------------#
+
+use strict;
+use warnings;
+use Const::Fast;
+use Scalar::Util::Numeric qw( isint );
+
+const my $DEFAULT_SIZE =>  4;
+const my $MAX_SIZE     => 39;   # Adjust for the target console
+
+$| = 1;
+
+MAIN:
+{
+    my $size   = $ARGV[0] // $DEFAULT_SIZE;
+    my $matrix = identity_matrix($size);
+
+    print "\nIdentity Matrix of size $size:\n";
+    print_matrix($matrix);
+}
+
+sub identity_matrix
+{
+    my ($size) = @_;
+
+    die "Invalid matrix size $size, stopped"
+         unless isint($size) && $size > 0;
+
+    die "Matrix size $size is too wide to be properly displayed, stopped"
+         if $size > $MAX_SIZE;
+
+    my $matrix;
+
+    for my $i (0 .. $size - 1)
+    {
+        $matrix->[$i][$_] = ($i == $_) ? 1 : 0 for 0 .. $size - 1;
+    }
+
+    return $matrix;
+}
+
+sub print_matrix
+{
+    my ($matrix) = @_;
+    my  $size    = scalar @$matrix;
+
+    if ($size == 1)
+    {
+        print '[', $matrix->[0][0], "]\n";
+    }
+    else
+    {
+        print '|', join( ' ', $matrix->[$_]->@* ), "|\n" for 0 .. $size - 1;
+    }
+}
+
+################################################################################