Array+Quiz

YOU CAN PRACTICE ARRAY HERE

1. Which of the following declares a reference to an array of int named cat?
 * a**. int cat;
 * b**. int[] cat;
 * c**. new int cat[];
 * d**. int img = int[];

2. What is the output of the following code fragment: code int[] cat = {2, 4, 6, 8 }; System.out.println( cat[0] + " " + cat[1] );

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

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

code int[] y = new int[10];

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

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

code

a. 34 88 0
 * b.** 34 88 88
 * c**. can't compile
 * d**. 0 34 88

4. What is the output of the following code fragment: code 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 ] );

code
 * a**. 43
 * b**. 37
 * c**. 1
 * d**. 9

5.How many objects are present after the following code fragment has executed? code double[] chris = new double[ 7 ]; double[] steve;

steve = chris;

code
 * a**. 2
 * b**.1
 * c**.14
 * d.** 7

6. What is the output of the following code fragment: code int[] x = new int[9];

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

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

code a. 7 3 0 b. 10 0 c. 7 3 4 d. 10 5

7. What is the output of the following code fragment: code int[] data = {0, 3, 7, 9, 12, 14};

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

code

a. 0 b. 3 c. 7 d.9

8. Does a programmer always know how long an array will be when the program is being written?

a.Yes---the program will not compile without the length being declared. b.No---the array object is created when the program is running, and the length might change from run to run c.Yes---otherwise the program will not run correctly d.No---arrays can grow to whatever length is needed

9. What is the length of the following array: byte[]data = { 12. 34. 35. 1. 0. 6 } ? a. 7 b. 8 c. 6 d. 12

10.) What is the output of the following code fragment: code   int[] helArray = { 2, 4, 6, 8, 10, 1, 3, 5, 7, 9 };

for ( int index= 0 ; index < helArray.length ; index++ ) System.out.print( helArray[ index ] + "  "  );

code a. 2 4 6 8 b. 2 4 6 8 10 c. 2 4 6 8 10 1 d. 2 4 6 8 10 1 3 5 7 9

11.) What is the length of the following array: byte[] data = { 12, 34, 9, 0, -62, 88 }; a. 5 b. 6 c. 4 d. 7

12.) Fill in the blank in the following code fragment so that each element of the array is assigned twice the value of its index. What does it prints?

int[] array = { 1, 4, 3, 6 }; int what = 0;

// scan the array for ( int index=0; index < array.length; index++ ) { what = what + array[ index ] ; } System.out.println( what );

a. 14 b. 1 c. 6 d. 1 4 3 6

1. b. 2. b. 3. a. 4. c. 5. b. 6. b. 7. d. 8. b. 9. c. 10. d. 11. b 12.a.
 * __CORRECT ANSWERS__**