gistfile1.pl

sub best_hit {
    ## Score
    $b->score <=> $a->score ||
        
    ## Identity
    $b->percent_id <=> $a->percent_id ||
    
    ## Length on query sequence
    (($b->hend-$b->hstart) <=>
     ($a->hend-$a->hstart)) ||
     
     ## Whatever
     rand() <=> rand()
}