how to calculate the address of the 2D array

Address of a[ i ][ j ]th element (row major)
*********************************************
 BA + [ n * ( i - LBR) + ( j - LBC) ] * w

                                                         Where BA = Base address
                                                               W = Number of bytes occupied by each element
                                                                 N = Number of columns


Address of a[ i ][ j ]th element (colum major)
*********************************************
     BA + [ ( i - LBR) + m * ( j - LBC) ] * w

                                                           Where BA = Base address
                                                                        W = Number of bytes occupied by each element
                                                                         N = Number of rows

 WHAT IS A 2D ARRAY?

 A matrix (two dimensional array) is a group of lists, or arrays that are organized into one data set. To understand them, first look an example of the standard one dimensional array:

Array "A":
16
8
99
0
5

You can reference any point in the "array" by naming the array and following it with a number representing the position of a piece of data on the list. The first data on the array is represented with a "0", the second with a "1", and so on. For example, A[2] (in bold) represents 99 because it is the third figure of array A. You could imagine the references of the above table as the following:

Array "A":
[0]
[1]
[2]
[3]
[4]

A matrix is a set of arrays. Visualize the following table:

Matrix "B":
16 17 9
8 88 74
99 12 21
0 6 40
5 19 18

There are 3 different arrays in a single data set, "B". In Array A, you could reference any data by naming the point on the list, such as "1" or "3". However, with a matrix, you must give both a row and a column. You can reference data on a matrix in the following format:

MatrixName[row][column]

For example, B[3][2] would represent 40 because it is the it is on the fourth row down and the third column. Remember, matrix references also start at zero, not one! You can reference any of the data on this table with this chart:

Matrix "B":
[0][0] [0][1] [0][2]
[1][0] [1][1] [1][2]
[2][0] [2][1] [2][2]
[3][0] [3][1] [3][2]
[4][0] [4][1] [4][2]

Two-dimensional arrays are used everywhere, but are especially prevalent in computer programming and accounting