From 623dc722f1be38a909baf7973e8cbbc8b317cd4c Mon Sep 17 00:00:00 2001
From: "Jaldhar H. Vyas" <jaldhar@braincells.com>
Date: Sat, 3 Aug 2019 18:41:15 -0400
Subject: Challenge 18 by Jaldhar H. Vyas: problem 1 and blog.

---
 challenge-018/jaldhar-h-vyas/blog.txt      |  1 +
 challenge-018/jaldhar-h-vyas/perl5/ch-1.pl | 29 +++++++++++++++++++++++++++++
 challenge-018/jaldhar-h-vyas/perl6/ch-1.p6 | 19 +++++++++++++++++++
 3 files changed, 49 insertions(+)
 create mode 100644 challenge-018/jaldhar-h-vyas/blog.txt
 create mode 100755 challenge-018/jaldhar-h-vyas/perl5/ch-1.pl
 create mode 100755 challenge-018/jaldhar-h-vyas/perl6/ch-1.p6

diff --git a/challenge-018/jaldhar-h-vyas/blog.txt b/challenge-018/jaldhar-h-vyas/blog.txt
new file mode 100644
index 0000000000..cfa3df0edd
--- /dev/null
+++ b/challenge-018/jaldhar-h-vyas/blog.txt
@@ -0,0 +1 @@
+https://www.braincells.com/perl/2019/08/perl_weekly_challenge_week_18.html
\ No newline at end of file
diff --git a/challenge-018/jaldhar-h-vyas/perl5/ch-1.pl b/challenge-018/jaldhar-h-vyas/perl5/ch-1.pl
new file mode 100755
index 0000000000..65b9b72876
--- /dev/null
+++ b/challenge-018/jaldhar-h-vyas/perl5/ch-1.pl
@@ -0,0 +1,29 @@
+#!/usr/bin/perl
+use warnings;
+use strict;
+use 5.010;
+
+sub LongestCommonSubstring {
+    my @strings = sort { length $a <=> length $b } @_;
+
+    my $shortest = shift @strings;
+    my @suffixes;
+    for my $i (0 .. length($shortest) - 1) {
+        for my $j ($i .. length($shortest) - 1) {
+            push @suffixes, substr $shortest, $i, $j - $i + 1;
+        }
+    }
+    @suffixes = reverse sort { length $a <=> length $b } @suffixes;
+
+    SUFFIX: for my $suffix (@suffixes) {
+        for my $string (@strings) {
+            if ( $string !~ /$suffix/) {
+                next SUFFIX;
+            }
+        }
+        return $suffix;
+    }
+}
+
+say LongestCommonSubstring('ABABC', 'BABCA', 'ABCBA');
+
diff --git a/challenge-018/jaldhar-h-vyas/perl6/ch-1.p6 b/challenge-018/jaldhar-h-vyas/perl6/ch-1.p6
new file mode 100755
index 0000000000..a8780681f5
--- /dev/null
+++ b/challenge-018/jaldhar-h-vyas/perl6/ch-1.p6
@@ -0,0 +1,19 @@
+#!/usr/bin/perl6
+
+sub LongestCommonSubstring(*@strings) {
+    @strings = @strings.sort(*.chars);
+
+    my $shortest = @strings.shift;
+    my @substrings;    
+    for 0 ..^ $shortest.chars -> $i {
+        for $i ..^ $shortest.chars -> $j {
+            @substrings.push($shortest.substr($i, $j - $i + 1));
+        }
+    }
+
+    return @substrings.sort(-*.chars)
+                    .grep({ @strings.all.contains($_) })
+                    .first;
+}
+
+say LongestCommonSubstring('ABABC', 'BABCA', 'ABCBA');
-- 
cgit