Yeah but look at this, it's a sample from my assignment;
As you can see it asks for the Section code (without 0 to exit) and then asks again with the zero to exit. How do I do that? :s
Enter the Section Code: 0
Invalid value entered. Must be 1 to 4, please re-enter: 1
Enter the Student's ID: 456789
Enter mark#1: 10
Enter mark#2: -20
Invalid grade entered. Must be 0.0 to 20.0, please re-enter: 20
Enter mark#3: 5.5
Enter mark#4: 5
Enter mark#5: 10
000456789's total mark is: 50.5
Enter the Student's ID ['0' to quit]: 123654987
Enter mark#1: 1
Enter mark#2: 2
Enter mark#3: 3
Enter mark#4: 4
Enter mark#5: 5
123654987's total mark is: 15.0
Enter the Student's ID ['0' to quit]: 0
The average for the section is 32.75%
Enter the Section Code [0 to quit]: 5