Merge pull request #5145 from simongreen-net/swg-137

sgreen solutions to challenge 137

4 files changed, 76 insertions, 2 deletions

diff --git a/challenge-137/sgreen/README.md b/challenge-137/sgreen/README.md
index a369799dbf..413edf3cdd 100644
--- a/challenge-137/sgreen/README.md
+++ b/challenge-137/sgreen/README.md
@@ -1,3 +1,3 @@
-# The Weekly Challenge 136
+# The Weekly Challenge 137
 
-Solution by Simon Green. [Blog](https://dev.to/simongreennet/weekly-challenge-136-12m7)
+Solution by Simon Green. [Blog](https://dev.to/simongreennet/weekly-challenge-137-3jon)
diff --git a/challenge-137/sgreen/blog.txt b/challenge-137/sgreen/blog.txt
new file mode 100644
index 0000000000..b8784a4f98
--- /dev/null
+++ b/challenge-137/sgreen/blog.txt
@@ -0,0 +1 @@
+https://dev.to/simongreennet/weekly-challenge-137-3jon
diff --git a/challenge-137/sgreen/perl/ch-1.pl b/challenge-137/sgreen/perl/ch-1.pl
new file mode 100755
index 0000000000..b834a9da94
--- /dev/null
+++ b/challenge-137/sgreen/perl/ch-1.pl
@@ -0,0 +1,39 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use feature 'say';
+
+sub _is_leap_year {
+    my $year = shift;
+    return 1 if $year % 400 == 0;
+    return 0 if $year % 100 == 0;
+    return 1 if $year % 4 == 0;
+    return 0;
+}
+
+sub main {
+    my @long_years = ();
+
+    # January 1st 1990 was a Monday
+    my $day_of_week = 1;
+    my $year        = 1900;
+
+    while ( $year <= 2100 ) {
+        my $leap = _is_leap_year($year);
+
+        # It's a long year if January 1st was a Thursday or Wednesday if
+        #   a leap year
+        if ( $day_of_week == 4 or ( $leap and $day_of_week == 3 ) ) {
+            push @long_years, $year;
+        }
+
+        # See you next year
+        $year++;
+        $day_of_week = ( $day_of_week + 1 + $leap ) % 7;
+    }
+
+    say join ', ', @long_years;
+}
+
+main();
diff --git a/challenge-137/sgreen/perl/ch-2.pl b/challenge-137/sgreen/perl/ch-2.pl
new file mode 100755
index 0000000000..9d0bd40b78
--- /dev/null
+++ b/challenge-137/sgreen/perl/ch-2.pl
@@ -0,0 +1,34 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use feature 'say';
+
+sub main {
+    my $n = shift;
+
+    # Sanity check
+    die "You must specify a number"               unless defined $n;
+    die "The value does not look like a number\n" unless $n =~ /^[0-9]+$/;
+    die "The value must be between 10 and 1,000"  unless $n >= 10 and $n <= 1000;
+
+    my $lychrel = 1;
+    my $count   = 0;
+    my $i       = $n;
+
+    while ( ++$count <= 500 and $i <= 10_000_000 ) {
+        my $r = reverse($i);
+        if ( $i == $r ) {
+            # The number is not lychrel-al (is that a word?)
+            $lychrel = 0;
+            last;
+        }
+
+        # Add the reverse to the original number, and repeat the test
+        $i += $r;
+    }
+
+    say $lychrel;
+}
+
+main(@ARGV);