12 files changed, 317 insertions, 5 deletions
diff --git a/challenge-270/packy-anderson/elixir/ch-2.exs b/challenge-270/packy-anderson/elixir/ch-2.exs
index 2904331718..ee1b9a420a 100755
--- a/challenge-270/packy-anderson/elixir/ch-2.exs
+++ b/challenge-270/packy-anderson/elixir/ch-2.exs
@@ -3,7 +3,7 @@
 defmodule PWC do
   # get just the indices stored in the map of maps
   defp indicesInMap(mapping) do
-    List.flatten( for i <- Map.values(mapping), do: Map.keys(i) )
+    List.flatten( for i <- Map.values(mapping), do: MapSet.to_list(i) )
   end
 
   def fmtInts(ints) do
@@ -11,13 +11,15 @@ defmodule PWC do
   end
 
   def addToMap(mapping, intVal, i) do
-    submap = Map.put(Map.get(mapping, intVal, %{}), i, 1)
+    submap = MapSet.put(Map.get(mapping, intVal, MapSet.new()), i)
     Map.put(mapping, intVal, submap)
   end
 
   def removeFromMap(mapping, intVal, i) do
-    submap = Map.delete(Map.get(mapping, intVal, %{}), i)
-    if submap == %{} do
+    submap = mapping
+    |> Map.get(intVal, MapSet.new())
+    |> MapSet.delete(i)
+    if MapSet.size(submap) == 0 do
       Map.delete(mapping, intVal)
     else
       Map.put(mapping, intVal, submap)
diff --git a/challenge-270/packy-anderson/raku/ch-2.raku b/challenge-270/packy-anderson/raku/ch-2.raku
index 897ddc89a2..0fc3db2d1d 100755
--- a/challenge-270/packy-anderson/raku/ch-2.raku
+++ b/challenge-270/packy-anderson/raku/ch-2.raku
@@ -92,3 +92,6 @@ solution([4,1], 3, 2);
 
 say "\nExample 2:";
 solution([2, 3, 3, 3, 5], 2, 1);
+
+say "\nExample Ergon:";
+solution([1,2,2], 3, 1);
diff --git a/challenge-271/packy-anderson/README.md b/challenge-271/packy-anderson/README.md
index 3f65972d0f..bfedb42a8d 100644
--- a/challenge-271/packy-anderson/README.md
+++ b/challenge-271/packy-anderson/README.md
@@ -20,4 +20,4 @@
 
 ## Blog Post
 
-[Bitwise Distribution](https://packy.dardan.com/b/LS)
+[Only Ones](https://packy.dardan.com/b/MC)
diff --git a/challenge-271/packy-anderson/blog.txt b/challenge-271/packy-anderson/blog.txt
new file mode 100644
index 0000000000..79befae346
--- /dev/null
+++ b/challenge-271/packy-anderson/blog.txt
@@ -0,0 +1 @@
+https://packy.dardan.com/b/MC
+\ No newline at end of file
diff --git a/challenge-271/packy-anderson/elixir/ch-1.exs b/challenge-271/packy-anderson/elixir/ch-1.exs
new file mode 100755
index 0000000000..c5223f3df3
--- /dev/null
+++ b/challenge-271/packy-anderson/elixir/ch-1.exs
@@ -0,0 +1,53 @@
+#!/usr/bin/env elixir
+
+defmodule PWC do
+  # we've exhasuted the matrix, return maxRow as 1-indexed value
+  def maximumOnes([], _, _, maxRow), do: maxRow + 1
+
+  def maximumOnes([row | matrix], rowNum, maxCount, maxRow) do
+    count = Enum.sum(row)
+    if count > maxCount do
+      # make the recursive call with this count and rowNum
+      maximumOnes(matrix, rowNum+1, count, rowNum)
+    else
+      # make the recursive call with the count and rowNum
+      # it was called with
+      maximumOnes(matrix, rowNum+1, maxCount, maxRow)
+    end
+  end
+
+  def maximumOnes(matrix) do
+    # set up the loop with initial values
+    maximumOnes(matrix, 0, -1, -1)
+  end
+
+  # default value for indent
+  def formatMatrix(matrix), do: formatMatrix(matrix, 17)
+
+  def formatMatrix(matrix, indent) do
+    output = for row <- matrix do
+      String.duplicate(" ", indent) <> "  [" <>
+      Enum.join(row, ", ") <> "]"
+    end
+    "[\n" <> Enum.join(output, ",\n") <> "\n" <>
+    String.duplicate(" ", indent) <> "]"
+  end
+
+  def solution(matrix) do
+    IO.puts("Input: $matrix = " <> formatMatrix(matrix))
+    IO.puts("Output: " <> to_string(maximumOnes(matrix)))
+  end
+end
+
+IO.puts("Example 1:")
+PWC.solution([ [0, 1],
+               [1, 0] ])
+
+IO.puts("\nExample 2:")
+PWC.solution([ [0, 0, 0],
+               [1, 0, 1] ])
+
+IO.puts("\nExample 3:")
+PWC.solution([ [0, 0],
+               [1, 1],
+               [0, 0] ])
diff --git a/challenge-271/packy-anderson/elixir/ch-2.exs b/challenge-271/packy-anderson/elixir/ch-2.exs
new file mode 100755
index 0000000000..fb7daad40a
--- /dev/null
+++ b/challenge-271/packy-anderson/elixir/ch-2.exs
@@ -0,0 +1,24 @@
+#!/usr/bin/env elixir
+
+defmodule PWC do
+  def bit_count(num) do
+    binary = Integer.to_string(num, 2)
+    String.length(Regex.replace(~r/0/, binary, ""))
+  end
+
+  def sortByHammingWeight(ints) do
+    Enum.sort_by(ints, &{ bit_count(&1), &1 })
+  end
+
+  def solution(ints) do
+    IO.puts("Input: @ints = (" <> Enum.join(ints, ", ") <> ")")
+    out = sortByHammingWeight(ints)
+    IO.puts("Output: (" <> Enum.join(out, ", ") <> ")")
+  end
+end
+
+IO.puts("Example 1:")
+PWC.solution([0, 1, 2, 3, 4, 5, 6, 7, 8])
+
+IO.puts("\nExample 2:")
+PWC.solution([1024, 512, 256, 128, 64])
diff --git a/challenge-271/packy-anderson/perl/ch-1.pl b/challenge-271/packy-anderson/perl/ch-1.pl
new file mode 100755
index 0000000000..c11fc91bb0
--- /dev/null
+++ b/challenge-271/packy-anderson/perl/ch-1.pl
@@ -0,0 +1,49 @@
+#!/usr/bin/env perl
+use v5.38;
+
+use List::Util qw( sum );
+
+sub maximumOnes($matrix) {
+  my ($maxCount, $maxRow) = (-1, -1);
+  foreach my $rowNum ( 0 .. $#{$matrix} ) {
+    my @row = @{ $matrix->[$rowNum] };
+    my $count = sum @row;
+    if ($count > $maxCount) {
+      $maxCount = $count;
+      $maxRow   = $rowNum;
+    }
+  }
+  # we're displaying rows 1-indexed
+  return $maxRow + 1;
+}
+
+sub formatMatrix($matrix, $indent=17) {
+  my @output;
+  foreach my $row (@$matrix) {
+    my $output_row = q{ } x $indent . "  [";
+    $output_row .= join(', ', map { sprintf "%1d", $_ } @$row) . ']';
+    push @output, $output_row;
+  }
+  return "[\n"
+       . join(",\n", @output)
+       . "\n"
+       . q{ } x $indent . "]";
+}
+
+sub solution($matrix) {
+  say 'Input: $matrix = ' . formatMatrix($matrix);
+  say 'Output: ' . maximumOnes($matrix);
+}
+
+say "Example 1:";
+solution([ [0, 1],
+           [1, 0] ]);
+
+say "\nExample 2:";
+solution([ [0, 0, 0],
+           [1, 0, 1] ]);
+
+say "\nExample 3:";
+solution([ [0, 0],
+           [1, 1],
+           [0, 0] ]);
diff --git a/challenge-271/packy-anderson/perl/ch-2.pl b/challenge-271/packy-anderson/perl/ch-2.pl
new file mode 100755
index 0000000000..f0b22e1417
--- /dev/null
+++ b/challenge-271/packy-anderson/perl/ch-2.pl
@@ -0,0 +1,33 @@
+#!/usr/bin/env perl
+use v5.38;
+
+use Memoize;
+memoize('bit_count');
+sub bit_count($num) {
+  # convert to binary
+  my $binary = unpack("B32", pack("N", $num));
+  # remove the 0s
+  $binary =~ s/0//g;
+  # what remains is just 1s
+  return length($binary);
+}
+
+sub sortByHammingWeight(@ints) {
+  return sort {
+    bit_count($a) <=> bit_count($b)
+    ||
+    $a <=> $b
+  } @ints;
+}
+
+sub solution(@ints) {
+  say 'Input: @ints = (' . join(', ', @ints) . ')';
+  my @out = sortByHammingWeight(@ints);
+  say 'Output: (' . join(', ', @out) . ')';
+}
+
+say "Example 1:";
+solution(0, 1, 2, 3, 4, 5, 6, 7, 8);
+
+say "\nExample 2:";
+solution(1024, 512, 256, 128, 64);
+\ No newline at end of file
diff --git a/challenge-271/packy-anderson/python/ch-1.py b/challenge-271/packy-anderson/python/ch-1.py
new file mode 100755
index 0000000000..144d150650
--- /dev/null
+++ b/challenge-271/packy-anderson/python/ch-1.py
@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+
+def maximumOnes(matrix):
+  maxCount = -1
+  maxRow   = -1
+  for rowNum, row in enumerate(matrix):
+    count = sum(row)
+    if count > maxCount:
+      maxCount = count
+      maxRow   = rowNum
+  # we're displaying rows 1-indexed
+  return maxRow + 1
+
+def formatMatrix(matrix, indent=17):
+    output = []
+    for row in matrix:
+        output_row = ' ' * indent + '  ['
+        output_row += ', '.join(map(lambda i: str(i), row))
+        output_row += ']'
+        output.append(output_row)
+
+    return(
+        "[\n" + ",\n".join(output) + "\n" +
+        ' ' * indent + ']'
+    )
+
+def solution(matrix):
+    print(f'Input: $matrix = {formatMatrix(matrix)}')
+    print(f'Output: { maximumOnes(matrix) }')
+
+print('Example 1:')
+solution([ [0, 1],
+           [1, 0] ])
+
+print('\nExample 2:')
+solution([ [0, 0, 0],
+           [1, 0, 1] ])
+
+print('\nExample 3:')
+solution([ [0, 0],
+           [1, 1],
+           [0, 0] ])
diff --git a/challenge-271/packy-anderson/python/ch-2.py b/challenge-271/packy-anderson/python/ch-2.py
new file mode 100755
index 0000000000..05d588853f
--- /dev/null
+++ b/challenge-271/packy-anderson/python/ch-2.py
@@ -0,0 +1,22 @@
+#!/usr/bin/env python
+
+def sortByHammingWeight(ints):
+  # use Decorate-Sort-Undecorate idiom
+  # (yes, it's a Schwartzian Transformation)
+  decorated = [ ( i.bit_count(), i ) for i in ints ]
+  decorated.sort()
+  return [ i for (bits, i) in decorated ]
+
+def comma_join(arr):
+    return ', '.join(map(lambda i: str(i), arr))
+
+def solution(ints):
+    print(f'Input: @ints = ({comma_join(ints)})')
+    out = sortByHammingWeight(ints)
+    print(f'Output: ({comma_join(out)})')
+
+print('Example 1:')
+solution([0, 1, 2, 3, 4, 5, 6, 7, 8])
+
+print('\nExample 2:')
+solution([1024, 512, 256, 128, 64])
+\ No newline at end of file
diff --git a/challenge-271/packy-anderson/raku/ch-1.raku b/challenge-271/packy-anderson/raku/ch-1.raku
new file mode 100755
index 0000000000..550982f834
--- /dev/null
+++ b/challenge-271/packy-anderson/raku/ch-1.raku
@@ -0,0 +1,47 @@
+#!/usr/bin/env raku
+use v6;
+
+sub maximumOnes(@matrix) {
+  my ($maxCount, $maxRow) = (-1, -1);
+  for @matrix.kv -> $rowNum, @row {
+    my $count = [+] @row;
+    if ($count > $maxCount) {
+      $maxCount = $count;
+      $maxRow   = $rowNum;
+    }
+  }
+  # we're displaying rows 1-indexed
+  return $maxRow + 1;
+}
+
+sub formatMatrix(@matrix, $indent=17) {
+  my @output;
+  for @matrix -> @row {
+    my $output_row = q{ } x $indent ~ "  [";
+    $output_row ~= @row.map({ sprintf "%1d", $_ })
+                       .join(', ') ~ "]";
+    @output.push($output_row);
+  }
+  return "[\n"
+       ~ @output.join(",\n")
+       ~ "\n"
+       ~ q{ } x $indent ~ "]";
+}
+
+sub solution(@matrix) {
+  say 'Input: $matrix = ' ~ formatMatrix(@matrix);
+  say 'Output: ' ~ maximumOnes(@matrix);
+}
+
+say "Example 1:";
+solution([ [0, 1],
+           [1, 0] ]);
+
+say "\nExample 2:";
+solution([ [0, 0, 0],
+           [1, 0, 1] ]);
+
+say "\nExample 3:";
+solution([ [0, 0],
+           [1, 1],
+           [0, 0] ]);
diff --git a/challenge-271/packy-anderson/raku/ch-2.raku b/challenge-271/packy-anderson/raku/ch-2.raku
new file mode 100755
index 0000000000..0043d7049a
--- /dev/null
+++ b/challenge-271/packy-anderson/raku/ch-2.raku
@@ -0,0 +1,36 @@
+#!/usr/bin/env raku
+use v6;
+
+use experimental :cached; 
+sub bit_count($num) is cached {
+  # convert to binary
+  my $binary = $num.Int.base(2);
+  # remove the 0s
+  $binary ~~ s:g/0//;
+  # what remains is just 1s
+  return $binary.chars;
+}
+
+sub sortFunction($a, $b) {
+  if    ( bit_count($a) > bit_count($b) ) { Order::More }
+  elsif ( bit_count($a) < bit_count($b) ) { Order::Less }
+  elsif ( $a > $b )                       { Order::More }
+  elsif ( $a > $b )                       { Order::Less }
+  else                                    { Order::Same }
+}
+
+sub sortByHammingWeight(@ints) {
+  return @ints.sort: { sortFunction($^a, $^b) };
+}
+
+sub solution(@ints) {
+  say 'Input: @ints = (' ~ @ints.join(', ') ~ ')';
+  my @out = sortByHammingWeight(@ints);
+  say 'Output: (' ~ @out.join(', ') ~ ')';
+}
+
+say "Example 1:";
+solution([0, 1, 2, 3, 4, 5, 6, 7, 8]);
+
+say "\nExample 2:";
+solution([1024, 512, 256, 128, 64]);
+\ No newline at end of file