Making Sure User Input is Correct

When you write programs, it’s really important to check what users input. This helps your program work well without crashing. Here’s how you can do this:

1. Check What Kind of Data It Is: Make sure the input is what you expect. For example, if you want a number, confirm that the input can be turned into a whole number.

   user_input = input("Enter a number: ")
   if user_input.isdigit():
       number = int(user_input)
   else:
       print("Please enter a valid number!")
   

2. Set Limits for Input: Decide on the acceptable range for inputs. For instance, if you want a grade between 0 and 100:

   grade = int(input("Enter your grade (0-100): "))
   if 0 <= grade <= 100:
       print("Grade accepted!")
   else:
       print("Please enter a grade between 0 and 100.")
   

3. Use Try-Except to Catch Errors: This can help you handle mistakes without your program stopping.

   try:
       age = int(input("Enter your age: "))
       print(f"Your age is {age}.")
   except ValueError:
       print("That's not a valid age!")
   

By using these tips, you can make your program easier for users and avoid problems that could make it stop working!