And just for fun, here's another way to do it using Tie::Array::Unique.

use Tie::Array::Unique;

my @a = (0,1,2,3,4,5,6,7);
my @b = (3,4,5,6,7,8,9,10);
tie my(@merged), 'Tie::Array::Unique', (@a,@b);
print join(',', @merged);
[download]

Will output 0,1,2,3,4,5,6,7,8,9,10.