APCSA Unit 6 Review Arrays

Which of the following is FALSE about arrays on Java

• A java array is an object

• Length of array can be changed after creation of array

• Numerical data types of arrays are initialized to 0 to start

Find the output

class Test {

public static void main(String args[]) {

int arr[2];

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

System.out.println(arr[1]);

}

}

• Compile error

• Exception

• Garbage Value

  Garbage Value

• 0

  0

Find the output

class Test {

public static void main(String args[]) {

int [ ] arr = new int[2];

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

System.out.println(arr[1]);

}

}

• Compile error

• Exception

• Garbage Value

  Garbage Value

• 0

  0

What is the length of the following array: int [] data = { 12, 34, 9, 0, -62, 88 };

• 1

• 5

• 6

• 12

Output of following Java program?

class Test{

public static void main (String[] args) {

int [] arr1 = {1, 2, 3};

int [] arr2 = {1, 2, 3};

if (arr1 == arr2)

System.out.println("Same");

else

System.out.println("Not same");

}}

• Same

• Not same

• Error

_________________ is a collection of elements used to store the same type of data.

• Array
• Switch
• Case
• Loop

What are the indexes for the array ar, given the following declaration:

int[] ar = {2, 4, 6, 8 }

•  0, 1, 2, 3
•  1, 2, 3, 4
• 2, 4, 6, 8
•  0, 2, 4, 6

What is returned by values[5]?

• 9
• 12
• 6
• 8

What is the error in the following code fragment?

double [] average = new double [20];

average[20] = 15.25;

• A cast is required

• data not initialized

• A two-dimensional array is required

• Array Out-of-bounds error

what is the result of :

nums[1]+nums[3]

• 3

• 14

• 6

• 5