Week 204 Task 2

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diff --git a/challenge-204/bob-lied/perl/ch-2.pl b/challenge-204/bob-lied/perl/ch-2.pl
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+#!/usr/bin/env perl
+# vim:set ts=4 sw=4 sts=4 et ai wm=0 nu:
+#=============================================================================
+# ch-2.pl Perl Weekly Challenge Week 204 Task 2 Reshape Matrix
+#=============================================================================
+# Copyright (c) 2023, Bob Lied
+#=============================================================================
+# You are given a matrix (m x n) and two integers (r) and (c).
+# Write a script to reshape the given matrix in form (r x c) with the
+# original value in the given matrix. If you can’t reshape print 0.
+# Example 1 Input: [ 1 2 ]
+#                  [ 3 4 ] $matrix = [ [ 1, 2 ], [ 3, 4 ] ]
+#                  $r = 1 $c = 4
+#          Output: [ 1 2 3 4 ]
+# Example 2 Input: [ 1 2 3 ]
+#                  [ 4 5 6 ] $matrix = [ [ 1, 2, 3 ] , [ 4, 5, 6 ] ]
+#                  $r = 3 $c = 2
+#          Output: [ [ 1, 2 ], [ 3, 4 ], [ 5, 6 ] ]
+# Example 3 Input: [ 1 2 ] $matrix = [ [ 1, 2 ] ]
+#                  $r = 3 $c = 2
+#          Output: 0
+#=============================================================================
+
+use v5.36;
+
+use Getopt::Long;
+my $Verbose = 0;
+my $DoTest  = 0;
+
+GetOptions("test" => \$DoTest, "verbose" => \$Verbose);
+exit(!runTest()) if $DoTest;
+
+sub usage() { qq(echo -e "[1,2] \\n [3,4]" | $0 r c ) }
+
+my $Row = shift;
+my $Col = shift;
+
+die 'Usage: '. usage() unless (defined $Row && $Row > 0) && (defined $Col && $Col > 0);
+
+my $input  = readMatrix();
+my $output = reshape($input, $Row, $Col);
+showMatrix($output);
+
+sub readMatrix()
+{
+    # Assuming one line per row, square brackets on the ends
+    # and possibly separated by commas
+    my @matrix;
+    while (<>)
+    {
+        chomp;
+        next if m/^\w*$/;   # Ignore blank lines
+        s/[[\],]/ /g;       # Leave only numbers
+        push @matrix, [ split ' ' ];    # Split on white space
+    }
+    return \@matrix;
+}
+
+sub reshape($matrix, $r, $c)
+{
+    showMatrix($matrix, "Input") if $Verbose;
+
+    my $origR = scalar(@$matrix);
+    my $origC = scalar( $matrix->[0]->@* );
+
+    return 0 if ( ($origR * $origC) != ($r * $c) );
+
+    my @flat = map { $_->@*  } $matrix->@*;
+
+    my @newMatrix;
+    push @newMatrix, [ splice(@flat, 0, $c) ] for 1 .. $r;
+    showMatrix(\@newMatrix, "Output") if $Verbose;
+    return \@newMatrix;
+}
+
+sub showMatrix($m, $title = "")
+{
+    my $row = scalar(@$m);
+
+    say $title;
+    for ( my $r = 0 ; $r < $row; $r++)
+    {
+        say +(' ' x length($title)), "[ ", join(", ", $m->[$r]->@*), " ]";
+    }
+}
+
+sub runTest
+{
+    use Test2::V0;
+
+    is( reshape( [ [1,2] ], 3, 2 ), 0, "Example 3");
+
+    is( reshape([ [1,2], [3,4] ], 1, 4), [ [ 1,2,3,4 ] ] , "Example 1");
+
+    is( reshape( [ [1,2,3], [4,5,6] ], 3, 2) , [ [1,2],[3,4],[5,6] ], "Example 2");
+
+    done_testing;
+}
+