Merge pull request #7847 from zapwai/branch-for-challenge-211

Week 211

2 files changed, 84 insertions, 0 deletions

diff --git a/challenge-211/zapwai/perl/ch-1.pl b/challenge-211/zapwai/perl/ch-1.pl
new file mode 100644
index 0000000000..13352b3e29
--- /dev/null
+++ b/challenge-211/zapwai/perl/ch-1.pl
@@ -0,0 +1,43 @@
+use v5.30.0;
+my @matrix = ( [4, 3, 2, 1],
+	       [5, 4, 3, 2],
+	       [6, 5, 4, 3], );
+# my @matrix = ( [1, 2, 3],
+#                    [3, 2, 1],
+#                  );
+my $m = $#matrix + 1;
+my $n = $#{$matrix[0]} + 1;
+say "Input: \@matrix is";
+for my $i (0 .. $m - 1) {
+    print " ";
+    for my $j (0 .. $n - 1) {
+	print $matrix[$i][$j];
+    }
+    print "\n";
+}
+my $flag = 1;
+for my $i (0 .. $m - 2) {
+    if ($i == 0) {
+	for my $j (0 .. $n - 2) {
+	    $flag = 0 unless (const_diag($i,$j));
+	}
+    } else {
+	$flag = 0 unless (const_diag($i,0));	
+    }
+}
+print "\nOutput: ";
+if ($flag) {
+    say "True, the matrix is Toeplitz.";
+} else {
+    say "False, the matrix is not Toeplitz.";
+}
+sub const_diag {
+    my ($i,$j) = @_;
+    my $val = $matrix[$i][$j];
+    for my $s ($i .. $m - 1) {
+	last if (!defined $matrix[$s][$j]);
+	return 0 unless ($matrix[$s][$j] == $val);
+	$j++;
+    }
+    1
+}
diff --git a/challenge-211/zapwai/perl/ch-2.pl b/challenge-211/zapwai/perl/ch-2.pl
new file mode 100644
index 0000000000..c08d3f84b0
--- /dev/null
+++ b/challenge-211/zapwai/perl/ch-2.pl
@@ -0,0 +1,41 @@
+use v5.30.0;
+my @nums = (1 .. 8);
+#my @nums = (1, 3);
+say "Input: \@nums = (@nums)";
+my $ans;
+my @subarrays;
+my $exp = $#nums + 1;
+for (1 .. (2**$exp) - 2) {
+    my $binary_number = sprintf '%'.$exp.'b', $_;
+    my @pips = split "", $binary_number;
+    my (@part1, @part2);
+    for my $i (0 .. $#nums) {
+	if ($pips[$i] == 1) {
+	    push @part1, $nums[$i];
+	} else {
+	    push @part2, $nums[$i];	    
+	}
+    }
+    my ($avg1, $avg2);
+    for my $elem (@part1) {
+	$avg1 += $elem;
+    }
+    for my $elem (@part2) {
+	$avg2 += $elem;
+    }
+    $avg1 = $avg1 / ($#part1 + 1);
+    $avg2 = $avg2 / ($#part2 + 1);    
+    #    say "@part1 - @part2 ~ $avg1 - $avg2";
+    if ($avg1 - $avg2 == 0) {
+	$ans = 1;
+	my $str = "(@part1)" . ' & ' . "(@part2) with avg $avg1";
+	push @subarrays, $str;
+    }
+}
+print "Output: ";
+if ($ans) {
+    say "true";
+    say "e.g. $subarrays[0]";    
+} else {
+    say "false";
+}