Merge pull request #12040 from adamcrussell/challenge-321

initial commit

6 files changed, 103 insertions, 0 deletions

diff --git a/challenge-321/adam-russell/blog.txt b/challenge-321/adam-russell/blog.txt
new file mode 100644
index 0000000000..5161a27edd
--- /dev/null
+++ b/challenge-321/adam-russell/blog.txt
@@ -0,0 +1 @@
+http://www.rabbitfarm.com/cgi-bin/blosxom/perl/2025/05/18
diff --git a/challenge-321/adam-russell/blog1.txt b/challenge-321/adam-russell/blog1.txt
new file mode 100644
index 0000000000..286d8c1845
--- /dev/null
+++ b/challenge-321/adam-russell/blog1.txt
@@ -0,0 +1 @@
+http://www.rabbitfarm.com/cgi-bin/blosxom/prolog/2025/05/18
diff --git a/challenge-321/adam-russell/perl/ch-1.pl b/challenge-321/adam-russell/perl/ch-1.pl
new file mode 100644
index 0000000000..dd59d22c05
--- /dev/null
+++ b/challenge-321/adam-russell/perl/ch-1.pl
@@ -0,0 +1,28 @@
+
+  
+use v5.40; 
+
+  
+  sub distinct_average{
+      my @numbers = 
+  sort {$a <=> $b} @_;
+
+      my %averages;
+      
+  for my $i (0 .. (@numbers / 2)){
+      my($x, $y) = ($numbers[$i], $numbers[@numbers - 1 - $i]);
+      $averages{
+  sprintf(q/%0.7f/, (($x + $y)/2))
+} = undef;
+  }
+
+      return 0 + keys %averages;
+  }
+
+  
+MAIN:{
+  say distinct_average 1, 2, 4, 3, 5, 6;
+  say distinct_average 0, 2, 4, 8, 3, 5;
+  say distinct_average 7, 3, 1, 0, 5, 9;
+}
+
diff --git a/challenge-321/adam-russell/perl/ch-2.pl b/challenge-321/adam-russell/perl/ch-2.pl
new file mode 100644
index 0000000000..8e1e347f09
--- /dev/null
+++ b/challenge-321/adam-russell/perl/ch-2.pl
@@ -0,0 +1,30 @@
+
+  
+use v5.40; 
+
+  
+  sub backspace_compare{
+      my($s, $t) = @_;
+      my @s = split //, $s;
+      my @t = split //, $t;
+      my @u = ();
+      my @v = ();
+      {
+          my $s_ = shift @s || undef;
+          my $t_ = shift @t || undef;
+          push @u, $s_ if $s_ && $s_ ne q/#/;
+          push @v, $t_ if $t_ && $t_ ne q/#/;
+          pop @u if $s_ && $s_ eq q/#/;
+          pop @v if $t_ && $t_ eq q/#/;
+          redo if @s || @t;
+      }
+      return join(q//, @u) eq join(q//, @v)?q/true/:q/false/;
+  }
+
+  
+MAIN:{
+  say backspace_compare q/ab#c/, q/ad#c/;
+  say backspace_compare q/ab##/, q/a#b#/;
+  say backspace_compare q/a#b/, q/c/;
+}
+
diff --git a/challenge-321/adam-russell/prolog/ch-1.p b/challenge-321/adam-russell/prolog/ch-1.p
new file mode 100644
index 0000000000..a1a9de95c0
--- /dev/null
+++ b/challenge-321/adam-russell/prolog/ch-1.p
@@ -0,0 +1,18 @@
+
+  
+  first_last([], []).
+  first_last(Numbers, FirstLastPairs):-
+      nth(1, Numbers, First),
+      last(Numbers, Last),
+      append([First|Rest], [Last], Numbers),
+      first_last(Rest, FirstLastPairs0),
+      append([[First, Last]], FirstLastPairs0, FirstLastPairs).
+
+  
+  distinct_average(Numbers, DistinctAverage):-
+      sort(Numbers, NumbersSorted),
+      first_last(NumbersSorted, MinimumMaximumPairs),
+      maplist(sum_list, MinimumMaximumPairs, MinimumMaximumSums),
+      sort(MinimumMaximumSums, MinimumMaximumSumsSorted),
+      length(MinimumMaximumSumsSorted, DistinctAverage).
+
diff --git a/challenge-321/adam-russell/prolog/ch-2.p b/challenge-321/adam-russell/prolog/ch-2.p
new file mode 100644
index 0000000000..82ce8c4ed7
--- /dev/null
+++ b/challenge-321/adam-russell/prolog/ch-2.p
@@ -0,0 +1,25 @@
+
+  
+  characters(Characters), [Characters] --> [Characters].
+  characters(C, Characters), [Characters] --> [C].
+
+  
+  process(String) --> characters(C, Characters),
+                      {String = [Code | Codes],
+                       last(C, PreviousCharacter),
+                       ((Code \== 35, char_code(C0, Code), 
+                       append(C, [C0], Characters));
+                       (append(Characters, [PreviousCharacter], C))), !},
+                      process(Codes).
+  process([]) --> [].
+
+  
+  backspace_compare(String1, String2):-
+      phrase(process(String1), [['']], [R1]),
+      delete(R1, '', R2),
+      atom_chars(Result1, R2),
+      phrase(process(String2), [['']], [R3]),
+      delete(R3, '', R4),
+      atom_chars(Result2, R4),
+      Result1 == Result2.
+