hi fellow monks!

please explain the enormous difference in computation time for the following two statements: 
my @data = ( 0 .. 50000);
my %hash = () ;

### version 1
map { $hash{$_}++ } @data;

### version 2
%hash = map { $_ => 1 } @data;

### version 3
### as fast as version 1
%hash = map { $_ => } @data

[download]
version 1 is about 100 times faster on my machine... i'm running 5.005_03 built for i386-linux.

thanks,
snowcrash //////

In reply to map efficiency by snowcrash

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