Please help me with this

Question

Write a C OR C++ program that calculates and prints the bill for a cellular telephone company. The company offers two types of service: regular and premium. Its rates vary, depending on the type of service. The rates are computed as follows:

Regular: $400.00 plus first 50 minutes are free. Charges for over 50 minutes are $8 per minute.
Premium: $25.00 plus for calls made from 6 am to 6 pm, the first 75 minutes are free; charges for more than 75 minutes are $4 per minute. For calls made from 6pm to 6am, the first 100 minutes are free; charges for more than 100 minutes are $2 per minute.Your program should prompt the user to enter a service type ( char), and the number of minutes the service was used. A service code of r or R means regular service; a service code of p or P means premium service. Treat any other character as an error. Your program should output the type of service, number of minutes the telephone service was used, and the amount due from the user.
For the premium service, 1 should input in hr

Answer 1

Your attempts?

Answer 2

#include <iostream>
#include <iomanip>

using namespace std;

const double REG_CHARGES = 400.00;
const int REG_MINUTES = 50;
const double REG_RATE_OVER_50 = 8;

const double PREM_SERV_CHARGES = 25.00;
const int PREM_FREE_DAY_MINUTES = 75;
const double PREM_DAY_RATE_OVER_75 = 4;

const int PREM_FREE_NIGHT_MINUTES = 100;
const double PREM_NIGHT_RATE_OVER_100 = 2;

double regular();
double premium ();

int main(void)
{

//Variable Declaration
int account;

char service_type;
double amount_due=0;

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

cout << "Enter Account Number" << endl;
cin >> account;

cout << "Enter Service Type: "
<< "R or r (Regular Service), "
<< "P or p (Premium Service): ";
cin >> service_type;

switch (service_type)
{
case 'r':
case 'R':

amount_due = regular();
cout << " Account Number = "
<< account << endl;
cout << "Amount Due = quot;
<< amount_due << endl;
break;