NOTE:

These are a little sketchy...I'll fill in details 'soon'.

Do NOT use a yes/no loop on a menu. Make 'quit' or 'done' or some-such a menu choice instead. When I choose quit from a program and it asks 'are you sure?', it just drives me nuts! It is nice once in a loooooooooooooooooooong while, but for the most part is just in the way...

At Least Once

• Positive:

      char again;
      do
      {
          /* do something */
          printf("\nWould you like to do _______ again?  ");
          scanf(" %c", &again);
      } while (tolower(again) == 'y');
  

• Negative:

      char again;
      do
      {
          /* do something */
          printf("\nAre we done with _______, finally?  ");
          scanf(" %c", &again);
      } while (tolower(again) == 'n');
  

Maybe Not At All

• Positive:

      char again;
      printf("Should we do _______?  ";
      scanf(" %c", &again);
      while (tolower(again) == 'y')
      {
          /* do something */
          printf("Should we do _______ again?  ";
          scanf(" %c", &again);
      }
  

• Negative:

      char again;
      printf("Should we do _______?  ";  /* can we ask this negatively?! */
      scanf(" %c", &again);
      while (tolower(again) == 'y')
      {
          /* do something */
          printf("Done with _______, yet?  ";
          scanf(" %c", &again);
          again = tolower(again) == 'n' ? 'y' : 'n';  /* flip sense for
                                                         loop control */
      }