Code:
int main()
{
Instructions(); // if needed
option = Menu();
switch(option)
{
case 1: // do stuff
.
.
.
default: // do stuff when incorect input is entered
}
//Continue outputting menus of options and inputting choices as much as needed
Calculations(/*variables go here*/);
Output(/*variables go here*/);
return 0;
}
There's something rough to get you started. It sounds to me like you just need to think this through using top-down design. Decompose your large problem into small problems that can be coded as functions. As a general rule, try to keep functions small enough so that you can view at least a whole one at once on your screen.
I don't know how else to help you. If you don't understand top-down design, you can search the web or buy a book. This seems like a really simple problem to me. If you need any specific help, ask a specific question in this forum. I hope this has helped you. Good luck