Week 252

2 files changed, 43 insertions, 0 deletions

diff --git a/challenge-252/cheok-yin-fung/perl/ch-1.pl b/challenge-252/cheok-yin-fung/perl/ch-1.pl
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+++ b/challenge-252/cheok-yin-fung/perl/ch-1.pl
@@ -0,0 +1,20 @@
+# The Weekly Challenge 252
+# Task 1 Special Numbers
+use v5.30.0;
+use warnings;
+use Math::Prime::Util qw/divisors/;
+
+sub sn {
+    my @ints = @_;
+    my @divisors = divisors(scalar @ints);
+    my $sum = 0;
+    for (@divisors) {
+        my $j = $_-1;
+        $sum += $ints[$j]*$ints[$j]
+    }
+    return $sum;
+}
+
+use Test::More tests=>2;
+ok sn(1,2,3,4)==21;
+ok sn(2, 7, 1, 19, 18, 3)==63;
diff --git a/challenge-252/cheok-yin-fung/perl/ch-2.pl b/challenge-252/cheok-yin-fung/perl/ch-2.pl
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+++ b/challenge-252/cheok-yin-fung/perl/ch-2.pl
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+# The Weekly Challenge 252
+# Task 2 Unique Sum Zero
+# Generate all combinations sum to zero, 
+# [optionally] given a lower bound and an upper bound 
+use v5.30.0;
+use warnings;
+use List::Util qw/sum/;
+use Algorithm::Combinatorics qw/combinations/;
+
+sub sz {
+    my $n = $_[0];
+    die "Invalid n\n" if $n <= 0;
+    my $lower = $_[1] || -$n;
+    my $upper = $_[2] || $n;
+    my @arr = ($lower..$upper);
+    my $iter = combinations(\@arr, $n);
+    while (my $c = $iter->next) {
+        my @com = $c->@*;
+        say "@com" if 0 == sum @com;
+    }
+}
+
+sz @ARGV || (5,-5,4);