Solve PWC219

3 files changed, 40 insertions, 0 deletions

diff --git a/challenge-219/wlmb/blog.txt b/challenge-219/wlmb/blog.txt
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+https://wlmb.github.io/2023/05/29/PWC219/
+
diff --git a/challenge-219/wlmb/perl/ch-1.pl b/challenge-219/wlmb/perl/ch-1.pl
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+#!/usr/bin/env perl
+# Perl weekly challenge 219
+# Task 1:  Sorted Squares
+#
+# See https://wlmb.github.io/2023/05/29/PWC219/#task-1-sorted-squares
+use v5.36;
+die <<~"FIN" unless @ARGV;
+    Usage: $0 -- N1 [N2...]
+    to square and sort the numbers N1 N2...
+    The -- is to allow negative numbers as arguments without
+    confusing them with options.
+    FIN
+say "@ARGV ->", join " ", sort {$a<=>$b} map {$_**2} @ARGV;
diff --git a/challenge-219/wlmb/perl/ch-2.pl b/challenge-219/wlmb/perl/ch-2.pl
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+#!/usr/bin/env perl
+# Perl weekly challenge 219
+# Task 2:  Travel Expenditure
+#
+# See https://wlmb.github.io/2023/05/29/PWC219/#task-2-travel-expenditure
+use v5.36;
+use List::Util qw(min);
+die <<~"FIN" unless @ARGV > 3;
+    Usage: $0 C1 C7 C30 D1 [D2...]
+    to calculate the travel expenditure for days D1, D2...
+    given the costs C1 C7 and C30 for one, seven and thirty day passes
+    FIN
+my @kinds=(1,7,30); # kinds of passes
+my @days=@ARGV;
+my @costs=splice @days, 0, 3;
+my $expenditure=cost(0, @days);
+say "Costs: @costs, Days: @days, Expenditure: $expenditure";
+
+sub cost($current, @days){
+    shift @days while @days and $current >= $days[0];
+    return 0 unless @days;
+    my $now=shift(@days);
+    my $cost=min map {$costs[$_]+cost($now+$kinds[$_]-1, @days)} 0..2;
+    return $cost;
+}