Chapter 6, Problem 37RQE

Function:

One of the building blocks of C++ program is functions; it contains a group of statements which are used to perform a specific task and the executable segments in a program.

• The function “main()” is most import function in a program, because the “main()” function is the starting point of the program.
• The main advantage of using function is reusability of code and reduces the size of the program, because a function can be called for multiple numbers of times.

Function call:

The statement which causes the function to execute is referred as function call.

• The function is called by its function name and the return type should not be specified before the function call.
• The semicolon should be given at the end of the function name.

Example:

//Function call

show();

In the above example, the function “show()” does not have the return type and it holds the semicolon at the end.

Function call for the given function:

The following function “getNumber()” uses the reference parameter variable which accepts an integer argument. It asks the user to enter the number and validates the entered number is in the range of 1 to 100. Finally, it stores input value in the parameter variable.

/* Function definition for a function "getNumber()" which uses the reference parameter variable which accepts an integer  argument */

void getNumber(int &x)

{

//Get the value from the user

cout << "Enter a number in the range 1 – 100 : ";

cin >> x;

//Check whether the given number is between 1-100

while (x < 1 || x > 100)

{

/* If the entered number is out of the given range then repeats the loop */

cout << "That number is out of range.\n";

cout << "Enter a number in the range 1 – 100 : ";

//Get the value from the user

cin >> x;

}

}

Algorithm:

Algorithm to implement a function with reference call is as follows:

• Start the program...