Task 1 PL/Perl done

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+-- Perl Weekly Challenge 191
+-- Task 1
+
+CREATE SCHEMA IF NOT EXISTS pwc191;
+
+
+/*
+testdb=> select * from pwc191.task1_plperl( ARRAY[1,2,3,6]::int[] );
+ task1_plperl 
+--------------
+            1
+
+*/
+CREATE OR REPLACE FUNCTION
+pwc191.task1_plperl( int[] )
+RETURNS int
+AS $CODE$
+   my ($l) = @_;
+
+   my $max = 0;
+
+   # compute the max element
+   for ( $l->@* ) {
+       $max = $_ if ( $max < $_ );
+   }
+
+   # iterate on all elements and see
+   # if one of the is doubly greater than the max
+   for ( $l->@* ) {
+       next if $_ == $max;
+       return -1 if $_ * 2 > $max;
+   }
+
+   return 1;
+$CODE$
+LANGUAGE plperl;