Core Java Programming Course- Two-dimensional (2D) Arrays

This video tutorial introduces the concept of two-dimensional arrays, contrasting them with single-dimensional arrays. It explains the structure of 2-D arrays as arrays of arrays, discusses how to determine their length, and compares them to tables. The tutorial also covers methods for retrieving and updating elements within 2-D arrays and demonstrates how to iterate over them using loops.

What is a two-dimensional array?

• An array with two indices

• An array of arrays

• An array with two elements

• An array with two data types

How does a 2-D array differ from a table?

• A table is always one-dimensional

• A 2-D array has a fixed number of columns

• A 2-D array can have varying column lengths

• A table can have varying row lengths

How can you find the length of the outer array in a 2-D array?

• Using arr[0].length()

• Using arr.length()

• Using arr[0].length

• Using arr.length

What happens if you try to access an element outside the boundaries of a 2-D array?

• It will return the last element

• The program will crash

• It will return null

• An index out of bound exception is thrown

Which method is used to iterate over a 2-D array?

• A single for loop

• A while loop

• A do-while loop

• A modified for loop

In a 2-D array, what does the inner loop iterate over?

• Rows

• Columns

• The entire array

• Elements within a row

What is the purpose of using a modified for loop in a 2-D array?

• To change the size of the array

• To iterate over each element in the array

• To sort the array

• To delete elements from the array