Language/Type: Java ArrayList Collections Author: Marty Stepp (on 2016/09/08)
Write a method swapPairs that switches the order of values in an ArrayList of Strings in a pairwise fashion. Your method should switch the order of the first two values, then switch the order of the next two, switch the order of the next two, and so on. For example, if the list initially stores these values: {"four", "score", "and", "seven", "years", "ago"} your method should switch the first pair, "four", "score", the second pair, "and", "seven", and the third pair, "years", "ago", to yield this list: {"score", "four", "seven", "and", "ago", "years"}
If there are an odd number of values in the list, the final element is not moved. For example, if the original list had been: {"to", "be", "or", "not", "to", "be", "hamlet"} It would again switch pairs of values, but the final value, "hamlet" would not be moved, yielding this list: {"be", "to", "not", "or", "be", "to", "hamlet"}
Language/Type: Java ArrayList Collections
Author: Marty Stepp (on 2016/09/08)
Write a method removeEvenLength that takes an ArrayList of Strings as a parameter and that removes all of the strings of even length from the list.
Type your solution here:
1. for (Iterator iterator = numbers. iterator(); iterator. hasNext();)
2. { Integer number = iterator. next();
3. if (number % 2 == 0) {
4. System. out. println("This is Even Number: " + number);
5. iterator. remove(); mtino
6
7
8 } This is a method problem.
Write a Java method as described. Do not write a complete program or class; just the method(s) above.
Language/Type: Java ArrayList Collections
Author: Marty Stepp (on 2016/09/08)
Write a method removeDuplicates that takes as a parameter a sorted ArrayList of Strings and that eliminates any duplicates from the list. For example, suppose that a variable called list contains the following values: {"be", "be", "is", "not", "or", "question", "that", "the", "to", "to"} After calling removeDuplicates (list); the list should store the following values: {"be", "is", "not", "or", "question", "that", "the", "to"}
Because the values will be sorted, all of the duplicates will be grouped together.
Type your solution here:
WN 600 O
This is a method problem. Write a Java method as described. Do not write a complete program or class; just the method(s) above.

public void swapPairs(ArrayList<String> list) {

   for(int i = 0; i <= list.size() - 2; i += 2) {        

       String val= list.get(i + 1);

       list.set(i + 1, list.get(i));

       list.set(i, val);     }   }          

Using the Iterator interface to remove the strings of even length from the list:

public void removeEvenLength( ArrayList<String> list) {

   Iterator<String> iter= list.iterator();

   while( iter.hasNext() ) {

       String str= iter.next();

       if( str.length() % 2 == 0 ) {

           iter.remove();         }     }   }

Not using Iterator interface:

public static void removeEvenLength(ArrayList<String> list) {  

   for (int i = 0; i < list.size(); i++) {

       String str= list.get(i);

       if (str.length() % 2 == 0) {

           list.remove(i);

           i--;         }     }  }

public static void removeDuplicates(ArrayList<String> list) {  

   for (int i = 0; i < list.size() - 1; i++) {

       if (list.get(i).equals(list.get(i + 1))) {

           list.remove(i + 1);

           i--;         }     }    }

Explanation:

a) The method swapPairs(ArrayList<String> list) ArrayList is used to store elements of String type. The for loop has a variable i that is initialized by 0. It moves through the list. This loop's body stops executing when the value of i exceeds the size-2 of the list. The size() method returns the size of the list. This means i stops moving through the list after the last pair of values is reached. In the loop body, get(i+1) method is used to obtain the element in the list at a index i+1. Lets say in the list {"four", "score", "and", "seven", "years", "ago"}, if i is at element "four" then i+1 is at "score". Then "score" is stored in val variable. Then set() method is used to set i-th element in an ArrayList object at the i+1 index position. The second set(i,val) method is used to set the value in val variable to i-th position/index. So this is how score and four are switched.

b) The method removeEvenLength( ArrayList<String> list) takes ArrayList of Strings as parameter. Iterator is an interface which is used to traverse or iterate through object elements and here it is used to remove the elements. The iterator() method is used to traverse through the array list. The while loop will keep executing till all the elements of the ArrayList are traversed. hasNext() method is used to return True if more elements in the ArrayList are to be traversed. next() method is used to return next element in the ArrayList and store that element in str variable. Then the if statement is used to check if the element in str variable is of even length. The length() function returns the length of the element in ArrayList and modulus is used to check if the length of the element is even. If the condition evaluates to true then the remove() method is used to remove that element of even length from the list.

c) The method removeDuplicates(ArrayList<String> list) takes ArrayList of Strings as parameter and eliminates any duplicates from the list. It has a for loop that moves through the list and it stops executing when the value of i exceeds the size - 1 of the list. The if condition has two method i.e. get() and equals(). The get() method is used to obtain the element at the specified index position and equals() function is used to compare the two string elements. Here these two strings are obtained using get() method. get(i) gets element at i-th index and get(i+1) gets element at i + 1 position of the list. If both these elements are equal, then the element at i+1 index is removed. This is how all duplicates will be removed.

we can all learn from our past mistakes because we all have different ways of learning different types of techniques. my way may or may not another classmate remember and have the repetition to acknowledge such standard. such as remembering acronyms. using abbreviations to us remember keep things in order in our memory. this us figure out what comes next in the sequence. if so, what we have is a sentence of just letters all in caps. we either know the meaning or have no idea what it stands for. most of the time we know the meaning and context. but most of us who don't know, should learn by having a quick glance at what needs to be remembered. such as repetition in the memory for acronyms. one way that me, is the fact that i'm always doing math and english assignments. so we have to remember specific meanings such as soapstone for documents, such as citing correctly. or pemdas for doing the equations correctly, even if it's the super long way. this works for everyone. you just have to find what works for you by practicing and repetition daily.