ch-2.pl

1 files changed, 59 insertions, 0 deletions

diff --git a/challenge-192/kueppo-wesley/Perl/ch-2.pl b/challenge-192/kueppo-wesley/Perl/ch-2.pl
new file mode 100644
index 0000000000..c2c4f1573a
--- /dev/null
+++ b/challenge-192/kueppo-wesley/Perl/ch-2.pl
@@ -0,0 +1,59 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+
+use Test::More;
+
+use List::Util qw/ sum /;
+
+sub equalize {
+    my @list = @_;
+    my $sum  = sum @list;
+
+    # Cannot equally distribute without using floating points, so return.
+    return -1 if $sum % @list != 0;
+
+    my $move   = 0;
+    my $target = $sum / @list;
+
+    while ( my ( $i, $v ) = each @list ) {
+
+        # Well, get this: no matter what, in the last iteration we are
+        # pretty pretty sure that `$v' is gonna be `$target'
+        next if $v == $target;
+
+        if ( $v < $target ) {
+            foreach my $j ( $i + 1 .. $#list ) {
+                if ( $list[$j] > $target ) {
+                    my $strip = $target - $v;
+
+                    $list[$j] -= $strip;
+                    $move += ( $j - $i ) * $strip;
+                    last;
+                }
+            }
+        }
+        else {
+            my $step = $v - $target;
+
+            $move += $step;
+
+            # and as a result we are never gonna overflow.
+            $list[ $i + 1 ] += $step;
+        }
+
+        $list[$i] = $target;
+    }
+
+    return $move;
+}
+
+my %test_data = (
+                  expected => [ 4,           -1,          2,           21 ],
+                  samples  => [ [ 1, 0, 5 ], [ 0, 2, 0 ], [ 0, 3, 0 ], [ 9, 9, 2, 4, 1 ] ],
+);
+
+is_deeply( [ map { equalize(@$_) } $test_data{samples}->@* ], $test_data{expected}, "Equalized?" );
+
+done_testing(1);