for ( @array )
    {
        if ( exists $hash{$_} )
        {
            push @found, $_ . $hash{$_};
        }
    }

##</code><code>##

    push @found, 
        map { $_ . $hash{$_} }
        grep { exists $hash{$_} }
        @array;

##</code><code>##

  push @found, map { exists $hash{$_} ? $_ . $hash{$_} : () } @array;