PCEP Control Flow, Loops, Lists and Logic Practice Question

A developer is writing a simple number guessing game. The computer picks a random number between 1 and 100, and the user keeps guessing until correct. The developer implements:

secret = random.randint(1,100) guess = 0

while guess != secret:

guess = int(input("Guess: "))

if guess == secret:
        print("Correct!")

else:

print("Wrong, try again.")

The game works, but the developer notices that if the user enters something that is not an integer, the program crashes. Which modification ensures the program handles non-integer input gracefully?

⚠ Common exam trap

Python Institute often tests the distinction between input validation (like `isdigit()`) and exception handling (`try-except`), where candidates mistakenly believe checking for digits is sufficient, ignoring that `int()` can still fail on valid-looking strings like '-5' or ' 10'.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Use a try-except around the input conversion

Wrapping the `int(input(...))` in a `try-except` block catches the `ValueError` that occurs when the user enters a non-integer string. This allows the program to handle the error gracefully (e.g., by printing a message and continuing the loop) instead of crashing. The other options do not prevent the crash when `int()` receives invalid input.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
Use a while True loop with break
Why it's wrong here
A while True loop with break changes loop control flow but leaves int(input(...)) unguarded, so ValueError still terminates the program on non-integer entry. It is tempting because it is the standard pattern for retry loops, and it would be correct if paired with try/except around the conversion.
✗
Change the data type of guess to string
Why it's wrong here
Declaring guess as a string makes the comparison guess != secret compare a string with an integer, which is always unequal, so the loop never terminates correctly. It is tempting because strings hold arbitrary text, and it would suit storing raw input before validation, not the numeric comparison itself.
✓
Use a try-except around the input conversion
Why this is correct
Wrapping the int(input(...)) conversion in try-except catches ValueError when non-numeric text is entered, letting the loop prompt again instead of crashing. This directly addresses the stem's constraint that non-integer input must be handled gracefully without terminating the guessing game.
✗
Add an if statement to check if input is digit
Why it's wrong here
isdigit() returns False for negative numbers and fails on whitespace or decimal strings, and it cannot prevent the int() call from raising ValueError on valid-looking but unconvertible input. It is tempting because it screens obvious non-numeric text, but the correct approach wraps int() in try/except to catch ValueError.

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PCEP Control Flow, Loops, Lists and Logic Practice Question

Why each option matters

Option-by-option breakdown

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