Configurable Length

Add a num parameter to run_quiz so players can choose how many questions to answer

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Ten questions is a longer round than three. Sometimes a player wants a quick five-question warmup, other times they want the full set. A num parameter makes the round length configurable without changing anything else.

Slicing

A slice takes the first num items from the list without modifying the original:

questions_for_round = questions[:num]

questions[:5] returns the first five questions. questions[:len(questions)] returns all of them.

None as a sentinel

num=None signals "not specified." The function checks for it and replaces it with len(questions):

def run_quiz(questions=QUESTIONS, num=None):
    if num is None:
        num = len(questions)

Calling run_quiz() with no arguments still works — it runs all questions.

Instructions

Add a num parameter to run_quiz and use slicing to limit the round.

Change the run_quiz signature from def run_quiz(questions=QUESTIONS): to def run_quiz(questions=QUESTIONS, num=None): — the None default means the caller can omit num and still get all questions.
At the top of run_quiz, add if num is None: num = len(questions) — this replaces the sentinel with the actual list length when no count was specified.
Replace total = len(questions) with total = len(questions_for_round), update the for loop to iterate over questions_for_round, and change print("=== Python Quiz ===") to print(f"=== Python Quiz ({total} questions) ===") — so the round uses only the sliced subset and the player sees the count upfront.

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QUESTIONS = [
    ("What is the type of the value 3.14?", "int", "str", "float", "bool", 3),
    ("What keyword defines a function in Python?", "for", "def", "if", "class", 2),
    ("What does print() do?", "Stores a value", "Returns a number", "Displays output", "Reads input", 3),
    ("What type does input() always return?", "int", "float", "str", "bool", 3),
    ("Which keyword starts a for loop?", "loop", "repeat", "for", "each", 3),
    ("What does len() return?", "The first item", "The last item", "The number of items", "The Sum", 3),
    ("What is the result of 10 // 3?", "3.33", "3", "1", "0", 2),
    ("Which keyword exits a loop early?", "exit", "return", "stop", "break", 4),
    ("What does elif stand for?", "else if", "elif loop", "end loop if", "extra loop", 1),
    ("What does a function return with no return statement?", "0", "False", "None", "Error", 3),
]

def ask_question(text, o1, o2, o3, o4, correct):
    print(text)
    print()
    print(f"  1) {o1}")
    print(f"  2) {o2}")
    print(f"  3) {o3}")
    print(f"  4) {o4}")
    print()
    while True:
        answer_text = input("Your answer (1-4): ")
        try:
            answer = int(answer_text)
        except ValueError:
            print("Please enter 1, 2, 3, or 4.")
            continue
        if answer < 1 or answer > 4:
            print("Please enter 1, 2, 3, or 4.")
            continue
        break
    is_correct = answer == correct
    print()
    print(f"You answered: {answer}")
    if is_correct:
        print("Correct!")
    else:
        print(f"Wrong! The correct answer was option {correct}.")
    return is_correct

def show_results(score, total):
    print(f"Score: {score}/{total}")
    if score == total:
        print("Perfect score!")
    elif score >= 2:
        print("Great job!")
    elif score >= 1:
        print("Not bad!")
    else:
        print("Keep practicing!")

# Step 1: Add num=None parameter to run_quiz
def run_quiz(questions=QUESTIONS):
    # Step 2: Add num check here
    total = len(questions)
    score = 0
    streak = 0
    print("=== Python Quiz ===")  # Step 4: show total in header
    print()
    # Step 3: Add questions_for_round = questions[:num]
    # Step 4: Update total and for loop to use questions_for_round
    for text, o1, o2, o3, o4, correct in questions:
        result = ask_question(text, o1, o2, o3, o4, correct)
        if result:
            score = score + 1
            streak = streak + 1
            if streak >= 3:
                print(f"  Hot streak! ({streak} in a row)")
        else:
            streak = 0
    show_results(score, total)

while True:
    run_quiz()
    print()
    again = input("Play again? (y/n): ")
    if again != "y":
        break

print("Thanks for playing!")

Configurable Length

Slicing

None as a sentinel

Instructions

Interactive Code Editor