in reply to Re^2: Proving Veritasiums riddle using Perl
in thread Proving Veritasiums riddle using Perl

Cool program. It's much faster using a shuffle.

Your code:

% time perl prisoners-orig.pl
== SIMULATION 9900 of 10000 ==
Success:   3085
Fail:      6915
Fail rate: 69.15%
perl prisoners-orig.pl  13.09s user 0.01s system 99% cpu 13.101 total

[download]

Modified to use Array::Shuffle:

% time perl prisoners.pl     
== SIMULATION 9900 of 10000 ==
Success:   3175
Fail:      6825
Fail rate: 68.25%
perl prisoners.pl  0.71s user 0.00s system 99% cpu 0.716 total

[download]

Diff:

--- prisoners-orig.pl    2025-04-30 17:24:41.190188166 -0400
+++ prisoners.pl    2025-04-30 17:24:01.156228637 -0400
@@ -7,7 +7,7 @@
 use warnings;
 use diagnostics;
 
-use Array::Contains;
+use Array::Shuffle qw(shuffle_array);
 
 my $PRISONERCOUNT = 100; # How many prisoners
 my $OPENBOXES = $PRISONERCOUNT / 2; # Every prisoner can open half th
+e boxes
@@ -49,15 +49,8 @@
 
 sub generateBoxes {
     print "Generating boxes...\n" if($DEBUG);
-    my @boxes;
-
-    while(scalar @boxes < $PRISONERCOUNT) {
-        my $prisoner = int(rand($PRISONERCOUNT));
-        if(!contains($prisoner, \@boxes)) {
-            push @boxes, $prisoner;
-        }
-    }
-
+    my @boxes = (0..$PRISONERCOUNT-1);
+    shuffle_array(@boxes);
     return \@boxes;
 }

[download]
90% of every Perl application is already written. ⇒
dragonchild

In Section Meditations