added solutions to 137

2 files changed, 76 insertions, 0 deletions

diff --git a/challenge-137/james-smith/perl/ch-1.pl b/challenge-137/james-smith/perl/ch-1.pl
new file mode 100644
index 0000000000..4ab92a0091
--- /dev/null
+++ b/challenge-137/james-smith/perl/ch-1.pl
@@ -0,0 +1,22 @@
+#!/usr/local/bin/perl
+
+use strict;
+
+use warnings;
+use feature qw(say);
+use Test::More;
+use Benchmark qw(cmpthese timethis);
+use Data::Dumper qw(Dumper);
+
+my $start_day = 1; ## Jan 1st 1900 was a Monday.
+
+foreach my $year ( 1900 .. 2100 ) {
+  my $is_leap_year = ! $year % 4 && ( $year % 100 || ! $year % 400 );
+  say $year if $start_day == 4 || $start_day == 3 && $is_leap_year;
+  $start_day = ( $start_day + 1 + $is_leap_year ) % 7;
+}
+
+## Compute if leap year?
+## Long year if starts on Thursday (day 4) or Wednesday (day 3) in a leap year
+## Next year starts on the next day of the week Mon->Tues ....
+##   except in a leap year when it moves 2 Mon->Wed
diff --git a/challenge-137/james-smith/perl/ch-2.pl b/challenge-137/james-smith/perl/ch-2.pl
new file mode 100644
index 0000000000..8951d7c972
--- /dev/null
+++ b/challenge-137/james-smith/perl/ch-2.pl
@@ -0,0 +1,54 @@
+#!/usr/local/bin/perl
+
+use strict;
+
+use warnings;
+use feature qw(say);
+use Test::More;
+use Benchmark qw(cmpthese timethis);
+use Data::Dumper qw(Dumper);
+
+my $MAX         = 1e9;
+my $MAX_LARGE   = 40;
+my $COUNT = 500;
+my @TESTS = (
+  [ 56, 0 ],
+  [ 57, 0 ],
+  [ 59, 0 ],
+  [196, 1 ],
+);
+
+is( lychrel(      $_->[0]), $_->[1] ) foreach @TESTS;
+is( lychrel_large($_->[0]), $_->[1] ) foreach @TESTS;
+
+done_testing();
+
+sub lychrel {
+  my($n,$c) = (shift,$COUNT);
+  ($n eq reverse $n) ? (return 0) : ($n+= reverse $n) while $c-- && $n <= $MAX;
+  1;
+}
+
+sub lychrel_large {
+  my($n,$c) = (shift,$COUNT);
+  my @n = split //, $n;
+  while( $c-- && @n <= $MAX_LARGE ) {
+    my @r = reverse @n;
+    return 0 if (join '', @r) eq (join '', @n);
+    foreach ( reverse 0 .. @n-1 ) {
+      $n[$_] += $r[$_];
+      next if $n[$_] < 10;
+      $n[$_]-=10;
+      $_ ? ($n[$_-1]++) : (unshift @n,1);
+    }
+  }
+  1;
+}
+
+
+print "Simple:";
+print " $_" foreach grep { lychrel $_ } 10..1000;
+print "\nLarge: ";
+print " $_" foreach grep { lychrel_large $_ } 10..1000;
+print "\n\n";
+