@foo = (1, 1, 1, 2, 3, 3, 3, 4, 5, 5, 6, 7, 8, 8, 9, 10); my @unique = sort {$a <=> $b} keys({map {$_ => 1} @foo}); print join(",", @unique) . "\n"; #### @foo = (1, 2, 3, 4, 5, 6, 7, 8, 9, 10); @bar = (0, 1, 2, 5, 7, 9, 11, 12, 13, 14); my @unique = sort {$a <=> $b} keys({map {$_ => 1} (@foo, @bar)}); print join(",", @unique) . "\n";