Question

Modify program 4-27 on page 219 as follows:

1) Add a new membership category for STUDENTS with a monthly rate of $90.00. The menu should have one more choice, and the switch statement should implement one more case.

2) The input for the number of months should be validated for 1 -36 months. No charges should be displayed for incorrect number of months. Instead, an error should be displayed similar with the one for wrong menu choice.

// This menu-driven program uses a switch statement to carry out

// the appropriate set of actions based on the user's menu choice.

#include <iostream>

#include <iomanip>

using namespace std;

int main()

{

// Constants for membership rates

const double ADULT_RATE = 120.0;

const double CHILD_RATE = 60.0;

const double SENIOR_RATE = 100.0;

int choice; // Menu choice

int months; // Number of months

double charges; // Monthly charges

// Display the menu and get the user's choice

cout << " Health Club Membership Menu\n\n";

cout << "1. Standard Adult Membership\n";

cout << "2. Child Membership\n";

cout << "3. Senior Citizen Membership\n";

cout << "4. Quit the Program\n\n";

cout << "Enter your choice: ";

cin >> choice;

// Validate and process the menu choice

if (choice >= 1 && choice <= 3)

{ cout << "For how many months? ";

cin >> months;

// Set charges based on user input

switch (choice)

{

case 1: charges = months * ADULT_RATE;

break;

case 2: charges = months * CHILD_RATE;

break;

case 3: charges = months * SENIOR_RATE;

}

// Display the monthly charges

cout << fixed << showpoint << setprecision(2);

cout << "The total charges are $" << charges << endl;

}

else if (choice != 4)

{ cout << "The valid choices are 1 through 4.\n";

cout << "Run the program again and select one of these.\n";

}

return 0;

}

Answer 1

Solution :

• Declare a constant double STUDENT_RATE equal to $90.0
• In the Switch case, add one more case for student membership.
• Validate months to be in the range 1 to 36.
• Add an error message using else statement, if entered month is not in the range 1 - 36

Following is the program for the same :

#include <iostream>

#include <iomanip>

using namespace std;

int main()

{

// Constants for membership rates

const double ADULT_RATE = 120.0;

const double CHILD_RATE = 60.0;

const double SENIOR_RATE = 100.0;

const double STUDENT_RATE = 90.0;

int choice; // Menu choice

int months; // Number of months

double charges; // Monthly charges

// Display the menu and get the user's choice

cout << " Health Club Membership Menu\n\n";

cout << "1. Standard Adult Membership\n";

cout << "2. Child Membership\n";

cout << "3. Senior Citizen Membership\n";

cout << "4. Student Membership\n";

cout << "5. Quit the Program\n\n";

cout << "Enter your choice: ";

cin >> choice;

// Validate and process the menu choice

if (choice >= 1 && choice <= 4)

{ cout << "For how many months? ";

cin >> months;

// Validate and process no. of months

if(months >=1 && months <= 36)

{
    
// Set charges based on user input

switch (choice)

{

case 1: charges = months * ADULT_RATE;

break;

case 2: charges = months * CHILD_RATE;

break;

case 3: charges = months * SENIOR_RATE;

break;

case 4: charges = months * STUDENT_RATE;

}

// Display the monthly charges

cout << fixed << showpoint << setprecision(2);

cout << "The total charges are $" << charges << endl;

}

else cout<<"The valid choices are 1 through 36.\n"; 

}

else if (choice != 4)

{ cout << "The valid choices are 1 through 4.\n";

cout << "Run the program again and select one of these.\n";

}

return 0;

}

Code demo :

Output 1:

Output 2 :