AP CSA Arrays and ArrayLists 2

Question 1

How do you find the number of elements in an ArrayList called `list`?

Accepted Answer

list.size()

Answer

list.length

Answer

list.length()

Answer

list.count()

Question 2

What is the result of `int[] arr = {3, 1, 4, 1, 5}; System.out.println(arr[2]);`?

Accepted Answer

4

Answer

1

Answer

3

Answer

5

Question 3

Which loop is most commonly used to iterate over every element in an array in AP CSA?

Accepted Answer

for-each (enhanced for loop)

Answer

while loop

Answer

do-while loop

Answer

indexed for loop only

Question 4

What does `list.remove(0)` do to an ArrayList?

Accepted Answer

Removes the element at index 0

Answer

Removes all elements equal to 0

Answer

Removes the last element

Answer

Throws an exception

Question 5

Which of these correctly initializes a 2D array with 3 rows and 4 columns?

Accepted Answer

int[][] grid = new int[3][4];

Answer

int[][] grid = new int[4][3];

Answer

int[3][4] grid = new int[][];

Answer

int grid[3][4];

Question 6

What is the output of: `int[] a = {10, 20, 30}; for(int x : a) System.out.print(x + " ");`

Accepted Answer

10 20 30

Answer

0 1 2

Answer

30 20 10

Answer

10, 20, 30,