Hello guys! i am new to this forum and i really need help with a program that i need to write for tomorrow, i am new to c++ and i really don't know where to start. can someone please help me..
this is the program i need to write:

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

Regular service: $10.00 base charge with first 50 minutes are free. Charges for over 50 minutes are $.20 per minute.

Premium service: $25.00 base with:

for calls made from 6:00am to 6:00pm, the first 75 minutes are free; charges for over 75 minutes are $.10 per minutes
for calls made from 6:00pm to 6:00am, the first 100 minutes are free; charges for over 100 minutes are $0.05 per minutes.
your program should prompt the user to enter an account number, a service code (type char), and the number of minutes of the service was used. A service code of r or R means regular service; a service code p or P means premium service. Treat any other character as error. Your program should output the account number, type of service, number of minutes the telephone service was used, and the amount due from the user.

For premium service, the customer may be using the service during the day and the night. Therefore, to calculate the bill, you must ask the user to input the number of minutes the service was used during the day and the number of minutes the service was used during the night.

The output should be nicely formatted. The amount due should be output with a '$' sign before the number and the number should be displayed with two digits after decimal point. ( for example, $45.50)

i know that you can't write the program for me but i need ideas of how to write it.

thanks for your help