Week 340 - Deduplicate and going up

3 files changed, 91 insertions, 0 deletions

diff --git a/challenge-340/peter-campbell-smith/blog.txt b/challenge-340/peter-campbell-smith/blog.txt
new file mode 100644
index 0000000000..2ada4532ac
--- /dev/null
+++ b/challenge-340/peter-campbell-smith/blog.txt
@@ -0,0 +1 @@
+http://ccgi.campbellsmiths.force9.co.uk/challenge/340
diff --git a/challenge-340/peter-campbell-smith/perl/ch-1.pl b/challenge-340/peter-campbell-smith/perl/ch-1.pl
new file mode 100755
index 0000000000..fd8b809f13
--- /dev/null
+++ b/challenge-340/peter-campbell-smith/perl/ch-1.pl
@@ -0,0 +1,49 @@
+#!/usr/bin/perl
+
+# Blog: http://ccgi.campbellsmiths.force9.co.uk/challenge
+
+use v5.26;    # The Weekly Challenge - 2025-09-22
+use utf8;     # Week 340 - task 1 - Duplicate removals
+use warnings; # Peter Campbell Smith
+binmode STDOUT, ':utf8';
+use Encode;
+
+duplicate_removals('abbaca');
+duplicate_removals('aaaaaaaa');
+duplicate_removals('abcdabcd');
+duplicate_removals('abcdeedcbaf');
+duplicate_removals('oodrrunggnpeellyyligoogcccazztfghhgfe');
+duplicate_removals('xabcdeedcbay');
+
+sub duplicate_removals {
+	
+	my ($string);
+	say qq[\nInput:   '$_[0]'];
+	
+	# imethod 1 - concise
+	$string = $_[0];
+	$string =~ s|$1$1|| while $string =~ m|([a-z])\1|;
+	say qq[Output1: '$string'];
+	
+	# method 2 - faster?
+	my ($last, $output, $j, $char);
+	
+	$string = $_[0];
+	$last = '#';
+	$output = '';
+	for $j (0 .. length($string) - 1) {
+		$char = substr($string, $j, 1);
+		
+		# this char same as last - discard both
+		if ($char eq $last) {
+			$output = substr($output, 0, -1);
+			$last = substr($output, -1);
+		
+		# this char differs from last - append it
+		} else {
+			$output .= $char;
+			$last = $char;
+		}
+	}
+	say qq[Output2: '$output'];
+}
diff --git a/challenge-340/peter-campbell-smith/perl/ch-2.pl b/challenge-340/peter-campbell-smith/perl/ch-2.pl
new file mode 100755
index 0000000000..0826a171c0
--- /dev/null
+++ b/challenge-340/peter-campbell-smith/perl/ch-2.pl
@@ -0,0 +1,41 @@
+#!/usr/bin/perl
+
+# Blog: http://ccgi.campbellsmiths.force9.co.uk/challenge
+
+use v5.26;    # The Weekly Challenge - 2025-09-22
+use utf8;     # Week 340 - task 2 - Ascending numbers
+use warnings; # Peter Campbell Smith
+binmode STDOUT, ':utf8';
+use Encode;
+
+ascending_numbers('the 1 cat sat on the 2 mats');
+ascending_numbers('the 2 cats sat on the 1 mat');
+ascending_numbers('the 3 cats sat on the 3 mats');
+ascending_numbers('one 1 two 2 three 3 four 4 five six 5 6 oops 5');
+ascending_numbers('0');
+ascending_numbers('cat');
+
+sub ascending_numbers {
+	
+	my ($string, $last);
+	
+	# initialise
+	$string = $_[0];
+	say qq[\nInput:  '$string'];
+	$last = -1;
+	
+	# loop over numbers
+	while ($string =~ m|(\d+)|g) {
+		
+		# ok
+		if ($1 > $last) {
+			$last = $1;
+			next;
+		}
+		
+		# not ok
+		say qq[Output: false ($1)];
+		return;
+	}
+	say qq[Output: true];
+}