Merge pull request #10768 from pjcs00/wk285

Week 285 - Dead end coins

3 files changed, 115 insertions, 0 deletions

diff --git a/challenge-285/peter-campbell-smith/blog.txt b/challenge-285/peter-campbell-smith/blog.txt
new file mode 100644
index 0000000000..5e8e341c9e
--- /dev/null
+++ b/challenge-285/peter-campbell-smith/blog.txt
@@ -0,0 +1 @@
+http://ccgi.campbellsmiths.force9.co.uk/challenge/285
diff --git a/challenge-285/peter-campbell-smith/perl/ch-1.pl b/challenge-285/peter-campbell-smith/perl/ch-1.pl
new file mode 100755
index 0000000000..b1dd302958
--- /dev/null
+++ b/challenge-285/peter-campbell-smith/perl/ch-1.pl
@@ -0,0 +1,51 @@
+#!/usr/bin/perl
+
+# Blog: http://ccgi.campbellsmiths.force9.co.uk/challenge
+
+use v5.26;    # The Weekly Challenge - 2024-09-02
+use utf8;     # Week 285 - task 1 - No connection
+use warnings; # Peter Campbell Smith
+binmode STDOUT, ':utf8';
+
+no_connection(['B', 'C'], ['D', 'B'], ['C', 'A']);
+no_connection(['F', 'G'], ['G', 'H'], ['H', 'F']);
+no_connection(['B', 'C'], ['A', 'A'], ['B', 'B']);
+
+# longer example - random routes
+my ($x, $y);
+for (0 .. 24) {
+	$x .= qq{['} . chr(int(rand(15)) + ord('A')) . qq{','} .
+		chr(int(rand(15)) + ord('A')) . qq{'],}
+}
+$x =~ s|.$||;
+no_connection(eval($x));
+
+sub no_connection {
+	
+	my (@routes, $r, $input, $output, %from, %to);
+	
+	# create list of froms and tos where from and to are distinct
+	@routes = @_;
+	for $r (@routes) {
+		$input .= qq{['$r->[0]', '$r->[1]'], };
+		next if $r->[1] eq $r->[0]; 
+		$from{$r->[0]} = 1;
+		$to{$r->[1]} = 1;
+	}
+	
+	# create list of froms and tos where from and to are distinct
+	$output = '';
+	for $r (@routes) {
+		next if $output =~ m|'$r->[1]'|;
+		$output .= qq['$r->[1]', ] unless defined $from{$r->[1]};
+	}
+	
+	# edge case of ['X', 'X']
+	for $r (@routes) {
+		if ($r->[1] eq $r->[0] and not $from{$r->[1]}) {
+			$output .= qq['$r->[1]', ] unless $output =~ m|'$r->[1]'|;
+		}
+	}
+	say qq[\nInput:  \@routes = (] . substr($input, 0, -2) . ')';
+	say qq[Output: ] . ($output ? substr($output, 0, -2) : 'none');
+}
diff --git a/challenge-285/peter-campbell-smith/perl/ch-2.pl b/challenge-285/peter-campbell-smith/perl/ch-2.pl
new file mode 100755
index 0000000000..f5b36cc871
--- /dev/null
+++ b/challenge-285/peter-campbell-smith/perl/ch-2.pl
@@ -0,0 +1,63 @@
+#!/usr/bin/perl
+
+# Blog: http://ccgi.campbellsmiths.force9.co.uk/challenge
+
+use v5.26;    # The Weekly Challenge - 2024-09-02
+use utf8;     # Week 285 - task 2 - Making change
+use warnings; # Peter Campbell Smith
+binmode STDOUT, ':utf8';
+
+making_change(9);
+making_change(15);
+making_change(100);
+making_change(500);
+
+sub making_change {
+	
+	my ($cents, $h, $q, $d, $n, $p, @sum, $count, $explain);
+	
+	# initialise
+	$cents = $_[0];
+	$count = 0;
+	$explain = '';
+	
+	# intelligently loop over all combs
+	H: for $h (0 .. 1e6) {
+		$sum[0] = $h * 50;
+		last H if $sum[0] > $cents;
+
+		Q: for $q (0 .. 1e6) {
+			$sum[1] = $sum[0] + $q * 25;
+			last Q if $sum[1] > $cents;
+
+			D: for $d (0 .. 1e6) {
+				$sum[2] = $sum[1] + $d * 10;
+				last D if $sum[2] > $cents;
+
+				N: for $n (0 .. 1e6) {
+					$sum[3] = $sum[2] + $n * 5;
+					last N if $sum[3] > $cents;
+
+					P: for $p (0 .. 1e6) {
+						$sum[4] = $sum[3] + $p;
+						
+						# found a valid combination
+						if ($sum[4] == $cents) {
+							$count ++;
+							$explain .= qq[  $count: ${h}H + ${q}Q + ${d}D + ${n}N + ${p}P\n];
+						}
+						last P if $sum[4] >= $cents;
+					}
+				}
+			}
+		}
+	}
+	
+	# output
+	say qq[\nInput:  \$cents = $cents];
+	$explain = qq[\n] if $count > 300;
+	$explain =~ s| \+ 0.||gm;
+	$explain =~ s|0H \+ ||gm;
+	print qq[Output: $count\n$explain];	
+}
+