Activity 1.14: Number Guessing Game

Activity 1.14

Number Guessing Game

Key Concepts

Sentinel-Controlled Loops

Looping Until the Right Answer

Not every loop counts a fixed number of times — some keep going until a specific value shows up. That value is called a sentinel.

score = 0

while score != -1:
    score = int(input("Enter a score (-1 to stop):"))
    # remaining code omitted

Today's Project

The computer picks a secret number from 1 to 10. The player keeps guessing — too high, too low — until they land on it.

Today's Objectives

Looping until the player guesses correctly
Giving feedback with an elif chain each pass through the loop
Counting how many tries it took

Key Terms

Sentinel Value: A specific value a loop watches for to know when to stop.

'F' → Fullscreen

Build

Create a new Python program named 1-14-number-guessing-game.

Task 1: Set Up the Game

Pick a random secret number from 1 to 10, and set up a guess and a tries counter.

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import random
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secret_number = random.randint(1, 10)
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guess = 0
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tries = 0

Task 2: The Guessing Loop

Loop until the guess matches the secret number, giving too-high/too-low feedback.

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import random
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secret_number = random.randint(1, 10)
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guess = 0
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tries = 0
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while guess != secret_number:
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    guess = int(input("Guess the number (1-10):"))
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    tries = tries + 1
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    if guess == secret_number:
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        print(f"Correct! It took you {tries} tries!")
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    elif guess > secret_number:
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        print("Wrong! Your guess was too high.")
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    elif guess < secret_number:
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        print("Wrong! Your guess was too low.")

Task 3: Handle Out-of-Range Guesses

Add a check for guesses outside 1-10, before the too-high/too-low checks.

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import random
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secret_number = random.randint(1, 10)
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guess = 0
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tries = 0
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while guess != secret_number:
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    guess = int(input("Guess the number (1-10):"))
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    tries = tries + 1
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    if guess == secret_number:
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        print(f"Correct! It took you {tries} tries!")
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    elif guess < 1 or guess > 10:
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        print("Your guess was out of range.")
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    elif guess > secret_number:
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        print("Wrong! Your guess was too high.")
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    elif guess < secret_number:
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        print("Wrong! Your guess was too low.")

Checkpoint

Verify your program works correctly.

Guess the number (1-10): 6 [Enter]
Wrong! Your guess was too high.
Guess the number (1-10): 3 [Enter]
Wrong! Your guess was too low.
Guess the number (1-10): 5 [Enter]
Wrong! Your guess was too high.
Guess the number (1-10): 4 [Enter]
Correct! It took you 4 tries!

Reflection

Answer the following questions before submitting your work.

What condition does the while loop check to decide whether to keep asking for another guess?
Why does guess need to start at a value like 0, which could never actually be the secret number?
Why didn't this activity need a final else branch to catch invalid input, the way the archive it's based on did?

Submit

Submit the required files to the appropriate dropbox.