Re: removing duplicated elements from array, with a difference

[krujos]

This is probably not the most efficient way to do this but it will work. This uses a hash to keep track of the duplicates.

my %hash;

my @NewArray; 
#read all of the values of the array into keys of the hash, 
#this eliminates all of the duplicates
foreach my $var (@OriginalArray) { 
   $hash{$var}=0;
}
#this loop marks any variable that appeared twice in the 
#original array. 
foreach my $var2 (@OriginalArray) {
   $hash{$var}++;
}
#This fills a new array based on the information from the 
#above loop
foreach my $var3 (keys (%hash)) { 
   if (!$hash{$var3} > 1) {
      print "$hash{$var3} deleted\n";
   } else { 
      $NewArray[@NewArray]=$hash{$var3};
   }
}
@OriginalArray = @NewArray;

update ++dpuu and thelenm for their much better and more efficient answers to this question.