You could try something like this: 
#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper::Simple;
use List::Util qw/shuffle/;

my @nums = (4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20);
my @shuffled_nums = shuffle(@nums);
my %extracted_nums;

for (0 .. 7) {
    $extracted_nums{$_} = shift @shuffled_nums;
}

print Dumper(%extracted_nums);
print Dumper(@shuffled_nums);

[download]
%extracted_nums will contain the numbers removed from the original list, and @shuffled_nums will contain those left over.

Is that what you wanted?

Cheers,
Darren

In reply to Re: getting random number 8 times never the same by McDarren
in thread getting random number 8 times never the same by Anonymous Monk

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