Week 306

2 files changed, 102 insertions, 0 deletions

diff --git a/challenge-306/zapwai/perl/ch-1.pl b/challenge-306/zapwai/perl/ch-1.pl
new file mode 100644
index 0000000000..dbfcb3622b
--- /dev/null
+++ b/challenge-306/zapwai/perl/ch-1.pl
@@ -0,0 +1,39 @@
+use v5.38;
+sub proc(@ints) {
+    say "Input: \@ints = @ints";
+    my $total = 0;
+    for my $o (1 .. @ints) {
+	next if ($o % 2 == 0);
+	my $last = @ints - $o;
+	for my $shift (0 .. $last) {
+	    my $sum = 0;
+	    my $n = $o;
+	    for my $i (1 .. $n) {
+		$sum += $ints[$shift + $i - 1];
+	    }
+	    $total += $sum;
+	}
+    }
+    # Read incorrectly the first time.
+    # Here is all subsets of odd length.
+    # for my $num (0 .. 2**@ints - 1) {
+    # 	my $form = "%0" . @ints . "b";
+    # 	my $x = sprintf($form, $num);
+    # 	my $count = 0;
+    # 	my @dig = split "", $x;
+    # 	for my $i (@dig) {
+    # 	    $count++ if ($i == 1);
+    # 	}
+    # 	next unless ($count % 2 == 1);
+    # 	my $sum = 0;
+    # 	for (0 .. $#dig) {
+    # 	  $sum += $ints[$_] if ($dig[$_] == 1);
+    # 	$total += $sum;
+    # }
+    say "Output: $total";
+}
+
+my @ints = (2,5,3,6,4);
+proc(@ints);
+@ints = (1,3);
+proc(@ints);
diff --git a/challenge-306/zapwai/perl/ch-2.pl b/challenge-306/zapwai/perl/ch-2.pl
new file mode 100644
index 0000000000..26ea7fd2ca
--- /dev/null
+++ b/challenge-306/zapwai/perl/ch-2.pl
@@ -0,0 +1,63 @@
+use v5.38;
+use List::Util qw( max );
+
+sub drop2($ind1, $ind2, @l) {
+	if ($ind1 > $ind2) {
+	    splice @l, $ind1, 1;
+	    splice @l, $ind2, 1;
+	} else {
+	    splice @l, $ind2, 1;
+	    splice @l, $ind1, 1;
+	}
+    
+    return @l;
+}
+
+sub churn(@l) {
+    my $max1 = max(@l);
+    my $max2 = 0;
+    my ($ind1, $ind2) = (0, 0);
+    my $found = 0;
+    for my $i (0 .. $#l) {
+	if ($found) {
+	    if ($max2 < $l[$i]) {
+		$max2 = $l[$i];
+		$ind2 = $i;
+	    }
+	} else {
+	    if ($l[$i] == $max1) {
+		$found = 1;
+		$ind1 = $i;
+		next;
+	    } else {
+		if ($max2 < $l[$i]) {
+		    $max2 = $l[$i];
+		    $ind2 = $i;
+		}
+	    }
+	}
+    }
+    $found = 0;
+    if ($max1 == $max2) {
+	@l = drop2($ind1, $ind2, @l);
+    } else {
+	my $newval = $max1 - $max2;
+	@l = drop2($ind1, $ind2, @l);
+	push @l, $newval;
+    }
+    return @l;
+}
+
+sub proc(@ints) {
+    say "Input: \@ints = @ints";
+    do {
+	@ints = churn(@ints);
+    } while (@ints > 1);
+    print "Output: ";
+    say $ints[0] // 0;
+}
+
+my @ints = (3, 8, 5, 2, 9, 2);
+proc(@ints);
+@ints = (3, 2, 5);
+proc(@ints);