# Quiz on Arrays

This is a practice quiz. The results are not recorded anywhere and do not affect your grade. The questions on this quiz might not appear in any quiz or test that does count toward your grade.

Instructions: For each question, choose the single best answer. Make your choice by clicking on its button. You can change your answers at any time. When the quiz is graded, the correct answers will appear in the box after each question.

1. Which of the following declares an array of int named img?

 a. int img; b. int[] img; c. new int img[]; d. int img = int[];

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

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

 a. 0, 1, 2, 3 b. 1, 2, 3, 4 c. 2, 4, 6, 8 d. 0, 2, 4. 6

3. What is the output of the following code fragment:

```int[] ar = {2, 4, 6, 8 };
System.out.println( ar[0] + " " + ar[1] );
```

 a. 2 6 b. 8 c. 2 4 d. 6 8

4. What is the output of the following code fragment:

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

ar[0] = 23;
ar[3] = ar[1];

System.out.println( ar[0] + " " + ar[3] );
```

 a. 23 2 b. 2 8 c. 31 d. 23 4

5. What is the output of the following code fragment:

```int[] y = new int[5];

y[0] = 34;
y[1] = 88;

System.out.println( y[0] + " " + y[1] + " " + y[5] );
```

 a. 34 88 0 b. 34 88 88 c. The program is defective and will not compile. d. 0 34 88

6. What is the output of the following code fragment:

```int[] z = new int[9];

z[0] = 7;
z[1] = 3;
z[2] = 4;

System.out.println( z[0] + z[1] + " " + z[5] );
```

 a. 10 0 b. 7 3 0 c. The program is defective and will not compile. d. 7 3 4

7. What is the output of the following code fragment:

```int[] zip = new int[5];

zip[0] = 7;
zip[1] = 3;
zip[2] = 4;
zip[3] = 1;
zip[4] = 9;

System.out.println( zip[ 2 + 1 ] );
```

 a. 4 3 b. 3 7 c. 4 d. 1

8. What is the output of the following code fragment:

```int[] zip = new int[5];

zip[0] = 7;
zip[1] = 3;
zip[2] = 4;
zip[3] = 1;
zip[4] = 9;

int j = 3;

System.out.println( zip[ j-1 ] );
```

 a. 7 b. 3 c. 4 d. 1

9. How many objects are present after the following code fragment has executed?

```double[] ann = new double[ 7 ];
double[] bob;

bob = ann;
```