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longestSortedSequence

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Author: Stuart Reges (on 2014/02/13)

Write a method longestSortedSequence that returns the length of the longest sorted sequence within a list of integers. For this problem sorted means non-decreasing. For example, if a variable called list stores the following sequence of values: 

        (1, 3, 5, 2, 9, 7, -3, 0, 42, 308, 17)

then the call: 

        list.longestSortedSequence()

would return the value 4 because it is the length of the longest sorted sequence within this list (the sequence -3, 0, 42, 308). If the list is empty, your method should return 0. Notice that for a non-empty list the method will always return a value of at least 1 because any individual element constitutes a sorted sequence.

You are writing a method for the IntList class discussed in lecture (handouts 3 and 5): 

        public class IntList {
                private int[] elementData; // list of integers
                private int size;          // current # of elements in the list

                <methods>
        }

You are not to call any other IntList methods to solve this problem. You also may not use another data structure like a temporary array and your method must run in O(n) time where n is the size of the list.

Write your solution to longestSortedSequence below.

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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