2D Arrays in Java (Review)

How many columns does a have if it is created as follows int[][] a = { {2, 4, 6, 8}, {1, 2, 3, 4}};?

• 2

• 3

• 4

• 8

Which of the following statements assigns the letter S to the third row and first column of a two-dimensional array named strGrid (assuming row-major order).

• strGrid[0][2] = "S";

• strGrid[1][3] = "S";

• strGrid[3][1] = "S";

• strGrid[2][0] = "S";

• strGrid[0][0] = "S";

How would you get the value 6 out of the following array int[][] a = { {2, 4, 6, 8}, {1, 2, 3, 4}};?

• a[0][3]

• a[1][3]

• a[0][2]

• a[2][0]

• a[3][1]

Given the following code segment, what is the value of sum after this code executes?

• 4

• 8

• 9

• 12

• 10

What are the contents of mat after the following code segment has been executed?

• { {2 3 3}, {1 2 3}, {1 1 2}, {1 1 1}}

• { {2 1 1}, {3 2 1}, {3 3 2}, {3 3 3}}

• { {2 1 1 1}, {3 2 1 1}, {3 3 2 1}}

• { {2 3 3 3}, {1 2 3 3}, {1 1 2 3}}

• { {1 1 1 1}, {2 2 2 2}, {3 3 3 3}}

Given the following code segment, what is the value of sum after this code executes?

• 4

• 9

• 6

• 10

• 20

What are the contents of arr after the following code has been executed?

• { {6, 4, 2}, {2, 4, 6}}

• { {3, 2, 1}, {1, 4, 6}}

• { {3, 2, 1}, {1, 4, 8}}

• { {4, 4, 2}, {2, 4, 4}}

• { {3, 2, 1}, {2, 4, 4}}

A two-dimensional array, imagePixels, holds the brightness values for the pixels in an image. The brightness can range from 0 to 255. What does the following method compute?

• The maximum brightness value for all pixels in imagePixel

• The column with the greatest brightness sum

• The most frequent brightness value in imagePixels

• The row with the greatest brightness sum

• The sum of the total brightness of imagePixels