- Added solutions by Javier Luque.

5 files changed, 215 insertions, 0 deletions

diff --git a/challenge-055/javier-luque/blog.txt b/challenge-055/javier-luque/blog.txt
new file mode 100644
index 0000000000..56430d807c
--- /dev/null
+++ b/challenge-055/javier-luque/blog.txt
@@ -0,0 +1 @@
+https://perlchallenges.wordpress.com/2020/04/06/perl-weekly-challenge-055/
diff --git a/challenge-055/javier-luque/perl/ch-1.pl b/challenge-055/javier-luque/perl/ch-1.pl
new file mode 100644
index 0000000000..c195f61949
--- /dev/null
+++ b/challenge-055/javier-luque/perl/ch-1.pl
@@ -0,0 +1,90 @@
+#!/usr/bin/perl
+# Test: ./ch-1.pl 2 3
+use strict;
+use warnings;
+use feature qw /say/;
+
+my $b = $ARGV[0];
+my $n = $ARGV[1];
+
+# Calculate $n if not supplied
+$n = int(log($b) / log(2)) + 1
+    unless($n);
+
+# Lets keep it to 1 to 32 bits and
+# throw out bits outside of our range
+$n = 32 if ($n > 32);
+$n = 1  if ($n < 1);
+my $mask = (2 ** $n - 1);
+$b = $b & $mask;
+
+# Print the original number
+say "ORIGINAL: " . sprintf("%0${n}B", $b) . "\n";
+
+# Store the solution;
+my %solutions;
+my $longest_soluton = 0;
+
+# flip algorithm
+for my $l (0 .. $n -1) {
+    for my $r ($l .. $n - 1) {
+        # We create two bit masks.
+        # The first mask is what we use to flip the bits
+        # and the second mask is what we use to keep the
+        # original builts then add up the flipped bits
+        # with the kept bits
+
+        # Flip Mask
+        my $flip_mask = 0;
+        for my $i ($l .. $r) {
+        	$flip_mask += (2 ** ($n - $i - 1) );
+        }
+
+        # Calculate the keep mask
+        my $keep_mask = (~ $flip_mask) & $mask;
+
+        # Flip the relevant bits and calculate kept bits
+        my $flipped_bits =  ~ ($b & $flip_mask) & $flip_mask;
+        my $kept_bits    = $b & $keep_mask;
+
+        # Add the bits outside the flipped bit
+        my $flipped_number = $flipped_bits + $kept_bits;
+
+        # Now store the number of ones
+        my $length = calculate_true_bits($flipped_number);
+
+        # Store the solutions
+        $solutions{$length} = []
+        	unless ($solutions{$length});
+
+        push @{$solutions{$length}}, {
+        	L      => $l,
+        	R      => $r,
+        	number => $flipped_number
+        };
+
+        # Length of the longest solution
+        $longest_soluton = $length
+        	if ($longest_soluton < $length);
+    }
+}
+
+# Print the solutions
+say "SOLUTIONS length($longest_soluton):";
+for my $solution (@{$solutions{$longest_soluton}}) {
+    say 'L: ' . $solution->{L} .
+        ' R: ' . $solution->{R} .
+        ' number: ' . sprintf("%0${n}B", $solution->{number});
+}
+
+# Calculate the number of true bits
+sub calculate_true_bits {
+    my $number = shift;
+    my $count = 0;
+
+    do {
+        $count++ if ($number & 1);
+    } while ($number = $number >> 1);
+
+    return $count;
+}
diff --git a/challenge-055/javier-luque/perl/ch-2.pl b/challenge-055/javier-luque/perl/ch-2.pl
new file mode 100644
index 0000000000..0658a75b6d
--- /dev/null
+++ b/challenge-055/javier-luque/perl/ch-2.pl
@@ -0,0 +1,27 @@
+#!/usr/bin/perl
+# Test: ./ch-1.pl 4
+use strict;
+use warnings;
+use feature qw /say/;
+use Algorithm::Combinatorics qw(permutations);
+
+my $n = $ARGV[0];
+my @array = (1 .. $n);
+
+# Permutations
+my $iter = permutations(\@array);
+
+# Loop through each combination
+while (my $p = $iter->next) {
+    my $is_wave = 1;
+
+    for (my $i = 1; $i < scalar(@$p); $i++) {
+    	if ( $i % 2 == 1 && $p->[$i] >= $p->[$i - 1] ||
+    	     $i % 2 == 0 && $p->[$i] <= $p->[$i - 1] ) {;
+    		$is_wave = 0;
+    		last;
+    	}
+    }
+
+    say join ' ', @$p if ($is_wave);
+}
diff --git a/challenge-055/javier-luque/raku/ch-1.p6 b/challenge-055/javier-luque/raku/ch-1.p6
new file mode 100644
index 0000000000..5fb8b9d065
--- /dev/null
+++ b/challenge-055/javier-luque/raku/ch-1.p6
@@ -0,0 +1,80 @@
+# Test: perl6 ch-1.p6 2 3
+
+multi MAIN(Int $b where * > 0) {
+    my $n = ((log($b) / log(2)) + 1).Int;
+    $n = 32 if ($n > 32);
+    MAIN($b, $n);
+}
+
+multi MAIN(Int $a where * > 0 , Int $n where 0 < * < 32) {
+    # Throw out bits outside of our range
+    my $mask = (2 ** $n - 1);
+    my $b = $a +& $mask;
+
+    # Original binary
+    say "ORIGINAL: " ~ sprintf("%0*b", $n, $b) ~ "\n";
+
+    # Store the solution;
+    my %solutions;
+    my $longest_solution = 0;
+
+    # flip algorithm
+    for (0 .. $n -1) -> $l {
+        for ($l .. $n - 1) -> $r {
+        	# Flip Mask
+        	my $flip_mask = 0;
+        	for ($l .. $r) -> $i {
+        		$flip_mask += (2 ** ($n - $i - 1) );
+        	}
+
+        	# Calculate the keep mask
+        	my $keep_mask = (+^ $flip_mask) +& $mask;
+
+        	# Flip the relevant bits and calculate kept bits
+        	my $flipped_bits =  +^ ($b +& $flip_mask) +& $flip_mask;
+        	my $kept_bits    = $b +& $keep_mask;
+
+        	# Add the bits outside the flipped bit
+        	my $flipped_number = $flipped_bits + $kept_bits;
+
+        	# Now store the number of ones
+        	my $length = calculate-true-bits($flipped_number);
+
+        	# Store the solutions
+        	%solutions{$length} = []
+        		unless (%solutions{$length});
+
+        	my %solution = 	(
+        		L      => $l,
+        		R      => $r,
+        		number => $flipped_number
+        	);
+
+        	%solutions{$length}.push(%solution);
+
+        	# Length of the longest solution
+        	$longest_solution = $length
+        		if ($longest_solution < $length);
+        }
+    }
+
+    say "SOLUTIONS length($longest_solution):";
+    for  (@(%solutions{$longest_solution})) -> $solution {
+        say 'L: ' ~ $solution{'L'} ~
+            ' R: ' ~ $solution{'R'} ~
+            ' Number: ' ~
+            sprintf("%0*b", $n, $solution{'number'});
+    }
+}
+
+# Calculate the number of true bits
+sub calculate-true-bits(Int $n is copy) {
+    my $count = 0;
+
+    repeat {
+        $count++ if ($n +& 1);
+    } while ($n = $n +> 1);
+
+    return $count;
+}
+
diff --git a/challenge-055/javier-luque/raku/ch-2.p6 b/challenge-055/javier-luque/raku/ch-2.p6
new file mode 100644
index 0000000000..e45180bb93
--- /dev/null
+++ b/challenge-055/javier-luque/raku/ch-2.p6
@@ -0,0 +1,17 @@
+# Test: perl6 ch-2.p6 4
+sub MAIN(Int $n where * > 0) {
+    [1 .. $n].permutations.grep({is-wave($_)}).join("\n").say;
+}
+
+# Is the array a wave
+sub is-wave(@n) {
+    my $is_wave = True;
+    loop (my $i = 1; $i < @n.elems; $i++) {
+    	if ( $i % 2 == 1 && @n[$i] >= @n[$i - 1] ||
+    	     $i % 2 == 0 && @n[$i] <= @n[$i - 1] ) {;
+    		$is_wave = False;
+    		last;
+    	}
+    }
+    return $is_wave;
+}