Changes to my Perl solutions to PWCC 268 from work, 2024-05-10_09-38.

2 files changed, 4 insertions, 7 deletions

diff --git a/challenge-268/robbie-hatley/perl/ch-1.pl b/challenge-268/robbie-hatley/perl/ch-1.pl
index 73353171fb..5f7860b760 100755
--- a/challenge-268/robbie-hatley/perl/ch-1.pl
+++ b/challenge-268/robbie-hatley/perl/ch-1.pl
@@ -44,6 +44,7 @@ PROBLEM NOTES:
 I'll sort both arrays then subtract the second from the first. If all elements of the difference are the same,
 that common value is our "magic number", otherwise return "none":
 
+   # Determine "magic number" (if any) for given matrix:
    sub magic ($matref) {
       my @row1 = sort {$a<=>$b} @{$$matref[0]};
       my @row2 = sort {$a<=>$b} @{$$matref[1]};
diff --git a/challenge-268/robbie-hatley/perl/ch-2.pl b/challenge-268/robbie-hatley/perl/ch-2.pl
index 690d1bb287..a97e2828e0 100755
--- a/challenge-268/robbie-hatley/perl/ch-2.pl
+++ b/challenge-268/robbie-hatley/perl/ch-2.pl
@@ -37,14 +37,10 @@ PROBLEM NOTES:
 This is equivalent to first sorting each array in increasing numeric order ("sort {$a<=>$b} @array"), then
 swapping pairs. Something like this:
 
+   # Reorder array of ints into a zigzagging ascending stairway:
    sub stairway (@array) {
-      my @zigzag = sort {$a<=>$b} @array;
-      for ( my $i = 0 ; $i <= $#zigzag - 1 ; $i += 2 ) {
-         my $temp = $zigzag[$i];
-         $zigzag[$i] = $zigzag[$i+1];
-         $zigzag[$i+1] = $temp;
-      }
-      return @zigzag;
+      my @sorted = sort {$a<=>$b} @array;
+      map {@sorted[2*$_+1,2*$_]} 0..($#sorted-1)/2;
    }
 
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