Chapter 8.11, Problem 8.21CP

Program Plan Intro

Two-dimensional array:

A two dimensional array is also called as a multi-dimensional array; a multidimensional array is that all the identical arrays are put together into a single array.

• This is useful for storing same type of multiple sets of data in same place.
• The main advantage is that one-dimensional array can hold only one set of value whereas two-dimensional array can hold multiple sets of data in the form of rows and columns.
• The structure of a multi-dimensional array is like a table (that is combination of rows and columns); it contains same type of columns.
• The array elements can be referred by the index numbers of the array; the index numbers for an “n x n” size array would be from “0, 0” to “n-1, n-1”.
  • For example, the index numbers of “3 x 3” array would be from “0, 0” to “2, 2” (that is (0, 0), (0, 1), (0, 2), (1, 0), (1, 1), (1, 2), (2, 0), (2, 1), and (2, 2)).

Example:

//Declaring multi-dimensional array

  double testmarks[5][5];

The above statement is used to create a multidimensional array with “5” rows and “5” columns; the first subscript (that is square bracket) is used to refer the number of rows and the second subscript is used to refer the number of columns.

• The data type “double” represents that the array will hold only “double” type of data.
• The “testmarks” array can hold 25 elements ($5\times 5=25$).