Programming help

Hi,

This is my first time posting to a 4Chan text board so i apologize if i seem a bit selfish asking for help in my first post but this is the only board that im confident has frequent users.

Here is my question:
For a homework assignment in C/C++ i need to have some code that will terminate the program if the user inputs a value outside of a preset range. Ive looked through the book and all the class notes i have and cant seem to find any reference on how to make that happen. I know someone here should be able to give me an idea on how to do this.

int inkey; int stpflg = 0;
do {
 printf("stuff"); inkey = getchar();
 switch inkey {
  case 'q' : stpflg = -1; break;
  }
} while (!stpflg)

better way:
for ( int stpflg = 0 ; stpflg = getchar() ; stpflg == 'q' ) { printf("stuff"); }