While using map certainly works, using map in a void context like you do is inefficient. Map returns an array for you regardless of whether you use it or not. As a result using map as a surrogate for loop is bad practice. In golf you use it because it is 2 chars shorter than a for loop. That is about the only (valid) reason to use it in a void context :-) All you actually want is: 

$help{$_}++ for @a

[download]

This is far more efficient, it is also shorter for what it's worth. Thanks to chipmunk for straigtening me out on this some months ago. 

my @a= (1,2,3,4,5,6,6,5,4,3,2,1);
my %help;
my @wasted_array = map { $help{$_}=1 } @a;
@a = keys %help;
print @wasted_array, "\n", @a;

[download]

cheers

tachyon

s&&rsenoyhcatreve&&&s&n.+t&"$'$`$\"$\&"&ee&&y&srve&&d&&print

In reply to Re: Re: Removing Duplicate Array Elements!!! by tachyon
in thread Removing Duplicate Array Elements!!! by dnickel

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