2 D Arrays

Question: Given a 2D array int[][] arr = new int[3][4], what is the index of the element located in the second row and third column?

• arr[2][1]

• arr[1][2]

• arr[2][3]

• arr[3][2]

Question: Which of the following code snippets correctly initializes a 2D array named matrix with 5 rows and 3 columns, where all elements are initially 0?

• int[][] matrix = new int[3][5];

• int[][] matrix = new int[5, 3];

• int[][] matrix = new int[5, 3][0];

• int[][] matrix = new int[5][3];

Consider the following code:

• 18

• 27

• 45

• 81

Write a Java method named transpose that takes a 2D integer array as input and returns a new 2D array that is the transpose of the original array. The transpose of a matrix is obtained by interchanging its rows with its columns.

Example:

int[][] original = {{1, 2, 3}, {4, 5, 6}};

The transposed array should be:

{{1, 4}, {2, 5}, {3, 6}}

Answer explanation

See the image!

Given a 2D integer array representing a matrix, write a Java method named findMax that returns the maximum value contained within the matrix.

Answer explanation