days 5-11

5/1.pl

@@ -0,0 +1,37 @@
+#!/usr/bin/perl
+
+use strict;
+use v5.10;
+use Data::Dumper;
+
+chomp (my @data = <STDIN>);
+@data = sort @data;
+
+foreach my $line (@data) {
+    say $line;
+    my @line = split //, $line;
+
+    my $pos = 0;
+    say $pos, "/", $#line;
+    while ( $pos < $#line ) {
+
+        if  (($line[$pos] =~ m/[A-Z]/) && ( lc($line[$pos]) eq $line[$pos+1] ) 
+                || ($line[$pos] =~ m/[a-z]/) && ( uc($line[$pos]) eq $line[$pos+1] ))  {
+            
+            #say "Cancelling ", $line[$pos], $line[$pos+1];
+
+            # Urgh, this is slow. 
+            if ($pos > 0) {
+                @line = (@line[ 0..$pos-1 ], @line[ $pos+2 .. $#line ]);
+            } else {
+                @line = @line[ $pos+2 .. $#line ];
+            }
+            $pos--;
+
+        } else {
+            $pos++;
+        }
+    }
+    say join("", @line);
+    print ($#line + 1);
+}