1.

2.

3.

4.

5.

7.

8.

In the circular array version of the Queue class, which operations require linear time for their worst-case behavior? A. poll B. insert when the capacity has not yet been reached C. isEmpty D. None of above Implement the following method as a new static method for the Node class. (Use the usual Node class with instance variables called data and next.) public static int count42s (Node head) // Precondition: head is the head reference of a linked list. // The list might be empty or it might be non-empty. // Postcondition: The return value is the number of occurrences // of 42 in the data field of a node on the linked list. // The list itself is unchanged. Please finish the following method which takes a string and checks whether the string is palindrome using stack. public static boolean checkPalindrome (String str) \{ \} Stack operations (push, pop, isEmpty) can be worst-case O(1 ) for a linked list implementation True False Suppose that the Foo class does not have an equals method. What happens when an expression x==y; is evaluated for two Foo objects? The expression is true if x and y refer to the same object The expression is true if x and y refer to objects with the same values Compiler error Run-time error What is the primary purpose of an Iterator object? To add new objects to a collection. To step through the objects of a collection one at a time. To play an audio clip. To display a graphical object. What is the value of the postfix expression 6324+ : Something between 15 and 100 Something between 5 and 15 Something between 5 and 5 Something between 5 and 15 Something between 15 and 100