Data commit

Task/Longest-common-substring/Perl/longest-common-substring-1.pl

@@ -0,0 +1,33 @@
+#!/usr/bin/perl
+use strict ;
+use warnings ;
+
+sub longestCommonSubstr {
+   my $first = shift ;
+   my $second = shift ;
+   my %firstsubs = findSubstrings ( $first );
+   my %secondsubs = findSubstrings ( $second ) ;
+   my @commonsubs ;
+   foreach my $subst ( keys %firstsubs ) {
+      if ( exists $secondsubs{ $subst } ) {
+	 push ( @commonsubs , $subst ) ;
+      }
+   }
+   my @sorted = sort { length $b <=> length $a } @commonsubs ;
+   return $sorted[0] ;
+}
+
+sub findSubstrings {
+   my $string = shift ;
+   my %substrings ;
+   my $l = length $string ;
+   for ( my $start = 0 ; $start < $l ; $start++ ) {
+      for ( my $howmany = 1 ; $howmany < $l - $start + 1 ; $howmany++) {
+	 $substrings{substr( $string , $start , $howmany) } = 1 ;
+      }
+   }
+   return %substrings ;
+}
+
+my $longest = longestCommonSubstr( "thisisatest" ,"testing123testing" ) ;
+print "The longest common substring of <thisisatest> and <testing123testing> is $longest !\n" ;

Task/Longest-common-substring/Perl/longest-common-substring-2.pl

@@ -0,0 +1,11 @@
+#!/usr/bin/perl
+
+use strict; # https://rosettacode.org/wiki/Longest_Common_Substring
+use warnings;
+
+my $one = 'thisisatest';
+my $two = 'testing123testing';
+
+my @best;
+"$one\n$two" =~ /(.+).*\n.*\1(?{ $best[length $1]{$1}++})(*FAIL)/;
+print "$_\n" for sort keys %{ $best[-1] };