sub sumTo {
    my $target = shift;
    ...
}

##</code><code>##

sub sumTo {
    my $target = shift;
    my @list = @_;
    if( $list[ 0 ] ) == $target ) 
        return 1;
    }
    return 0;
}

##</code><code>##

sub sumTo {
    my $target = shift;
    for( @_ ) {
        if( $_ ) == $target ) 
            return 1;
        }
    }
    return 0;
}

##</code><code>##

sub sumTo {
    my $target = shift;
    for( 0 .. $#_ ) {
        if( $_[ $_ ] == $target )
            return 1;
        }
        else {
            if( sumTo( $target - $_[$_], @_[0 .. $_-1, $_+1 .. $#_] ) ) {
                return 1;
            }
        }
    }
    return 0;
}

##</code><code>##

@_[0 .. $_-1, $_+1 .. $#_]