Perl solution for week 111, part 2

2 files changed, 84 insertions, 1 deletions

diff --git a/challenge-111/abigail/README.md b/challenge-111/abigail/README.md
index def177b2a6..5f00924966 100644
--- a/challenge-111/abigail/README.md
+++ b/challenge-111/abigail/README.md
@@ -10,7 +10,6 @@
 
 ### Notes
 
-
 ### Solutions
 
 ### Blog
@@ -24,7 +23,34 @@
 > Write a script to find the longest English words that don't change when
 > their letters are sorted.
 
+### Notes
+We will grep the words from standard input which don't change
+if they are sorted; these are the words which match the pattern
+/^a*b*c*...z*$/i. We keep track of the longest word.
+
+If course, there does not have to be a unique word. It will depend
+on the word list used to search in. For instance, three different
+word list I used give different results:
+
+    infochimps.com     /usr/share/dict/words     enable.lst
+    --------------     ---------------------     ----------
+                                     Adelops
+          aegilops
+                                     alloquy
+                                     beefily        beefily
+                                     begorry
+                                     billowy        billowy
+                                     egilops
+
+Only one of them has a unique longest word.
+
+We will be reading a word list from standard input, and write
+the longest word where the letters are in alphabetical order
+to standard output. In case of ties, we print the first one found.
+
+
 ### Solutions
+* [Perl](perl/ch-2.pl)
 
 ### Blog
 
diff --git a/challenge-111/abigail/perl/ch-2.pl b/challenge-111/abigail/perl/ch-2.pl
new file mode 100644
index 0000000000..5f4041c69c
--- /dev/null
+++ b/challenge-111/abigail/perl/ch-2.pl
@@ -0,0 +1,57 @@
+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# See ../README.md
+#
+
+#
+# Run as: perl ch-2.pl < word-list
+#
+
+#
+# We will grep the words from standard input which don't change
+# if they are sorted; these are the words which match the pattern
+# /^a*b*c*...z*$/i. We keep track of the longest word.
+#
+# If course, there does not have to be a unique word. It will depend
+# on the word list used to search in. For instance, three different
+# word list I used give different results:
+#
+#    infochimps.com     /usr/share/dict/words     enable.lst
+#    --------------     ---------------------     ----------
+#                                     Adelops
+#          aegilops
+#                                     alloquy
+#                                     beefily        beefily
+#                                     begorry
+#                                     billowy        billowy
+#                                     egilops
+#
+# Only one of them has a unique longest word.
+#
+
+#
+# We will be reading a word list from standard input, and write
+# the longest word where the letters are in alphabetical order
+# to standard output. In case of ties, we print the first one found.
+#
+
+
+my $pat = join "" => map {"$_*"} 'a' .. 'z';
+
+my $longest = "";
+
+while (<>) {
+    $longest = $_ if /^$pat$/i && length ($_) > length ($longest)
+}
+
+print $longest;