JDVP Activity

What is the ArrayList nums if it is initially [5, 3, 1] and the following code is executed?

nums.add(6);

nums.add(0, 4);

nums.remove(1);

• [4, 3, 1, 6]

• [5, 3, 1, 6]

• [4, 3, 6]

• [4, 5, 3, 6]

Which statement below is the correct way to retrieve the first element in the nums ArrayList?

• nums.get(0)

• nums[0]

• nums(0)

• nums[1]

Given the ArrayList nums with the values [3, 7, 6, 0], what code below is the proper way to change the 7 to be a 5?

• nums.set(1, 5)

• nums.set(7, 5)

• nums.set(5, 2)

• nums[2] = 5

Given the nums ArrayList with the values [5, 4, 3, 2], what statement below removes the value 3 from the list?

• nums.remove(2)

• nums.remove(3)

• nums.get(2) = null

• nums.remove(1)

Given the nums ArrayList with the values [1, 2, 3, 4, 6], what code below can be used to add a 5 between the 4 and 6 in the list?

• nums.add(4, 5)

• nums.add(5, 4)

• nums.add(5, 5)

• nums.add(5)

What will print when the following code executes?

ArrayList<Integer> list = new ArrayList<Integer>();

list.add(7);

list.add(8);

list.add(9);

System.out.println(list.remove(0));

• 7

• 8

• 9

• 0

What is printed?

ArrayList<Integer> alist;

alist = new ArrayList<Integer>();

alist.add(1);

alist.add(2);

alist.remove(1);

alist.add(1, 3);

alist.set(1, 4);

alist.add(5);

System.out.println(alist);

• [1, 4, 5]

• [1, 4, 3, 5]

• [2, 4, 5]

• [2, 4, 3, 5]

What is printed?

ArrayList<Double> vals;

vals = new ArrayList<Double>();

vals.add(3.5);

vals.add(4.5);

vals.add(5.5);

vals.set(0, 2.5) ;

System.out.println(vals);

• [2.5, 4.5, 5.5, 3.5]

• [2.5, 3.5, 4.5, 5.5]

• [3.5, 4.5, 5.5, 2.5]

• [2.5, 4.5, 5.5]

Which statement is the correct declaration and initialization of an ArrayList of String values?

• ArrayList<String> name;

  name = new ArrayList<String>();

• ArrayList name;

  name = new ArrayList<String>();

• ArrayList<String> name;

  name = ArrayList<String>();

• String<ArrayList> name;

  name = new String<ArrayList>();

What is the primary difference between ArrayList and LinkedList in Java?

• ArrayList uses a dynamic array, while LinkedList uses a doubly linked list.

• ArrayList uses a static array, while LinkedList uses a dynamic array.

• ArrayList and LinkedList are identical in implementation.

• ArrayList uses a singly linked list, while LinkedList uses a doubly linked list.