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BJP4 Exercise 16.5: countDuplicates

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Author: Whitaker Brand (on 2016/09/08)

Write a method countDuplicates that returns the number of duplicates in a sorted list. The list will be in sorted order, so all of the duplicates will be grouped together. For example, if a variable list stores the sequence of values below, the call of list.countDuplicates() should return 7 because there are 2 duplicates of 1, 1 duplicate of 3, 1 duplicate of 15, 2 duplicates of 23 and 1 duplicate of 40: 

[1, 1, 1, 3, 3, 6, 9, 15, 15, 23, 23, 23, 40, 40]

Remember that you may assume that the list is in sorted order, so any duplicates would occur consecutively.

Assume that you are adding this method to the LinkedIntList class as defined below: 

public class LinkedIntList {
    private ListNode front;   // null for an empty list
    ...
}
Type your solution here:


This is a partial class problem. Submit code that will become part of an existing Java class as described. You do not need to write the complete class, just the portion described in the problem.

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