def two_number_sum_pointers(array, target_sum):
    """
        two_number_sum_pointers finds the two numbers whose sum is equals to target_sum
        with the pointers strategy

        array: the collection of numbers that can sum the target number.
        target_num: the target number to find

        returns a list with the two numbers that sums the target number.
        if there are not number that can sum the target, it returns an empty list.

    """
    for i in range(len(array) - 1):
        first_num = array[i]
        
        for j in range(i + 1, len(array)):
            second_num = array[j]
            if first_num + second_num == target_sum:
                return [first_num, second_num]
    return []