Remove consecutive duplicate elements

Problem statement

Write a C++ program that, given a linked list of characters, removes all the elements in the list that are immediately preceded by an element with the same data. In other words, after executing your code, the list should not contain any consecutive duplicates (non-consecutive duplicates need not be deleted). All elements remaining in the linked list must appear in their original order.

As shown in the test cases below, your code may assume that the pointers head and tail are initialized to the first and last nodes of the linked list, respectively, or to NULL when the linked list is empty. This invariant must still hold after execution of your code. Note that two additional pointers p1 and p2 are declared. For this exercise, you may not declare any additional pointers.

Make sure that your code works on all possible linked lists. The following 8 test cases are provided to help you test your code.

Test case #1

Description: The linked list is empty.

Initial setup:

Final configuration:

Ready to test your program?

Remove consecutive duplicate elements

Problem statement

Test case #1

Test case #2

Test case #3

Test case #4

Test case #5

Test case #6

Test case #7

Test case #8