How to create an efficient java code using Greedy algorithm to solve the problem?

Hello, i need help with understanding Big-O.   What is the execution time Big-O for each of the methods in the Queue-1.java interface for the  ArrayQueue-1.java  and   CircularArrayQueue-1.java implementations? Short Big-O reminders: Big-O is a measure of the worst case performance (in this case execution time). O(1) is constant time (simple assignment statements) O(n) is a loop that iterates over all of the elements. O(n2) is one loop nested in another loop, each of which iterates over all the elements. If a method calls another method, what happens in the called method must be taken into consideration. Queue.java public interface Queue<E> {    /**      * The element enters the queue at the rear.      */    public void enter(E element);     /**      * The front element leaves the queue and is returned.      * @throws java.util.NoSuchElementException if queue is empty.      */    public E leave();     /**      * Returns True if the queue is empty.      */    public boolean…

Java Programming Big O question

39, question is in Java, thanks