Question

Write a loop that asks the user "Do you want to repeat the program or quit? (R/Q)". The loop should repeat until the user has entered an \(\mathrm{R}\) or \(\mathrm{Q}\) (either uppercase or lowercase).

Short answer

(R/Q): ") if user_input in ['R', 'r']: print("Repeating the program...") elif user_input in ['Q', 'q']: print("Quitting the program...") ```

Step-by-step solution

Create the while loop

Start by creating a while loop that will run until the user enters one of the specified characters ('R', 'r', 'Q', or 'q'). We will use the 'input()' function to accept the user's input and store it in a variable. ```python user_input = '' while user_input not in ['R', 'r', 'Q', 'q']: user_input = input("Do you want to repeat the program or quit? (R/Q): ") ```

Process the user input

Inside the while loop, we don't need to perform any additional actions, since the only purpose of this loop is to ensure the user enters a valid input. Once the user enters a valid input, the loop will automatically exit. Here is the complete code: ```python user_input = '' while user_input not in ['R', 'r', 'Q', 'q']: user_input = input("Do you want to repeat the program or quit? (R/Q): ") if user_input in ['R', 'r']: print("Repeating the program...") elif user_input in ['Q', 'q']: print("Quitting the program...") ``` With these steps, we have created a loop that takes user input until it receives a valid input, either to repeat the program or quit.