- Added solution by Sol DeMuth.

2 files changed, 80 insertions, 0 deletions

diff --git a/challenge-048/sol-demuth/README b/challenge-048/sol-demuth/README
new file mode 100644
index 0000000000..c1899409dc
--- /dev/null
+++ b/challenge-048/sol-demuth/README
@@ -0,0 +1 @@
+Solutions by Sol DeMuth.
diff --git a/challenge-048/sol-demuth/perl/ch-2.pl b/challenge-048/sol-demuth/perl/ch-2.pl
new file mode 100644
index 0000000000..797229a128
--- /dev/null
+++ b/challenge-048/sol-demuth/perl/ch-2.pl
@@ -0,0 +1,79 @@
+#!/usr/bin/perl
+
+use strict;
+use warnings;
+
+my $leapDay         = '0229';
+my ($minYr, $maxYr) = (2000, 2999);
+my @palDates        = ();
+
+my $mm = '01';
+my $dd = '01';
+
+while ($mm < 13) {
+    my $yr = validYear("$mm$dd");
+
+    if ($yr) {
+        push @palDates, "$mm$dd$yr";
+    }
+
+    incr(\$dd);
+
+    if (monthLength($mm) < $dd) {
+        # special leap case
+        if ("$mm$dd" eq $leapDay) {
+            my $yr = validYear($leapDay);
+
+            if (isLeap($yr)) {
+                push @palDates, "$leapDay$yr";
+                warn "LEAP! $mm$dd$yr\n\n";
+            }
+        }
+
+        # roll monthy/day
+        incr(\$mm);
+        $dd = '01';
+    }
+}
+
+foreach my $dt (sort { yyyymmdd($a) <=> yyyymmdd($b) } @palDates) {
+    print $dt . "\n";
+}
+
+sub incr { # zero-padded increment
+    ${$_[0]} = sprintf '%02d', ${$_[0]} + 1;
+}
+
+sub isLeap { # doesn't merit datetime
+    my ($year) = @_;
+
+    return $year && (!($year % 4) && (!!($year % 100) || !($year % 400)));
+}
+
+sub monthLength { # nucks (we don't need datetime...)
+    my $mm    = sprintf '%02d', $_[0];
+    my $moLen = 31;
+
+    if ($mm == 2) {
+        $moLen = 28;
+    } elsif ($mm =~ /^(?:04|06|09|11)$/) {
+        $moLen = 30;
+    }
+
+    return $moLen;
+}
+
+sub validYear { # palindrome test
+    my $yr = join('', reverse split('', $_[0]));
+
+    if (
+           $yr >= $minYr
+        && $yr <= $maxYr
+    ) {
+        return $yr;
+    }
+}
+
+sub yyyymmdd { # for sorting output
+    return substr($_[0], 4, 4) . substr($_[0], 0, 4);
+}