Merge pull request #12604 from wlmb/challenges

Solve PWC337

3 files changed, 44 insertions, 0 deletions

diff --git a/challenge-337/wlmb/blog.txt b/challenge-337/wlmb/blog.txt
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+https://wlmb.github.io/2025/08/31/PWC337/
diff --git a/challenge-337/wlmb/perl/ch-1.pl b/challenge-337/wlmb/perl/ch-1.pl
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+++ b/challenge-337/wlmb/perl/ch-1.pl
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+#!/usr/bin/env perl
+# Perl weekly challenge 337
+# Task 1:  Smaller Than Current
+#
+# See https://wlmb.github.io/2025/08/31/PWC337/#task-1-smaller-than-current
+use v5.36;
+use PDL;
+use PDL::NiceSlice;
+die <<~"FIN" unless @ARGV;
+    Usage: $0 A1 A2...
+    to find for each number Ni in the array Ak how many numbers Nj
+    are less than Ni.
+    The arrays are input as strings of the form
+    "[N0 N1 ...]" where the Ni's are numbers
+    FIN
+for(@ARGV){
+    my $array=pdl($_);
+    say "$_ -> ",($array(*1)>$array)->sumover; # compare array as cols vs. as rows
+}
diff --git a/challenge-337/wlmb/perl/ch-2.pl b/challenge-337/wlmb/perl/ch-2.pl
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+#!/usr/bin/env perl
+# Perl weekly challenge 337
+# Task 2:  Odd Matrix
+#
+# See https://wlmb.github.io/2025/08/31/PWC337/#task-2-odd-matrix
+use v5.36;
+use PDL;
+use PDL::NiceSlice;
+use feature qw(try);
+die <<~"FIN" unless @ARGV and @ARGV%3==0;
+    Usage: $0 R1 C1 P1 R2 C2 P2...
+    to find how many odd numbers are in a matrix of Ri rows and Ci columns
+    after the rows and columns corresponding to the points Pi are incremented,
+    where Pi is input as a string with the format "[[r1 c1][r2 c2]...]"
+    FIN
+for my($rows,$cols,$points)(@ARGV){
+    try {
+	my $matrix=zeroes($cols,$rows);
+	my $locations=pdl($points);
+	$matrix(($_))++ for $locations->slice("(1)")->dog;  # increment columns
+	$matrix(,($_))++ for $locations->slice("(0)")->dog; # increment rows
+	say "Rows=$rows, Cols=$cols, Locations=$points -> ", ($matrix%2)->sum
+    } catch($e) { say $e;}
+}