Bootcamp Day 3 - Java Array

Which of the following is the correct way to declare a multidimensional array in Java?

• int array(5,5);

• int[][] array = new int[5][5];

• int array[] = new int[5,5];

• array int[][] = new array[5][5];

What is the default value of elements in a newly declared array of type double in Java?

• 0

• 0.0

• Garbage value

• null

Identify the correct statement for the following code:

int arr[] = new int[5];

System.out.println(arr[5]);

• Prints 0

• Prints null

• Compilation error

• Runtime ArrayIndexOutOfBoundsException

Which of the following statements correctly creates and initializes an array?

• int arr[] = new int();

• int arr[] = new int[5]{1,2,3,4,5};

• int arr[] = {1,2,3,4,5};

• int[] arr = new int[5] = {1,2,3,4,5};

Which of the following array declarations is invalid?

• char[] ch = new char[10];

• float arr[] = new float[];

• boolean[] flags = new boolean[2];

• String[] names = {"John", "Doe"};

What will the following code output?

int[] a = {1, 2, 3};

int[] b = a;

b[0] = 10;

System.out.println(a[0]);

• 1

• 10

• Compilation Error

• 0

What does Arrays.toString(arr) return for arr = new int[]{3, 4, 5}?

• "[3 4 5]"

• "3, 4, 5"

• "[3, 4, 5]"

• {3, 4, 5}

How many elements does the array int[][] mat = new int[4][3]; contain?

• 7

• 12

• 4

• 3

Which Java method is best suited to sort an array of integers?

• Collections.sort()

• Arrays.sort()

• Math.sort()

• System.sort()

What is the size of the array declared as String[] arr = new String[5];?

• 4

• 5

• 0

• Undefined