Python Project: Guess the Number

What you are building

You build a small game. The program holds a secret integer from 1 to 20. Each guess is compared to that secret. The player hears too high, too low, or correct. When the match happens, the program prints how many attempts it took.

Copy every example into the Python editor at /try and click Run. That editor is Python only. It is not HTML, C, or C++. The complete program uses a list of guesses so it prints a full playthrough without waiting for input().

Skills used

• if / elif / else to compare a guess to the secret
• A for loop over a list of demo guesses
• A counter that goes up on every attempt
• random.randint when you later want a new secret each run
• break to stop as soon as the player wins

Compare one guess

Start with three numbers: a low bound, a high bound, and a secret. Then test a single guess. The comparison is the whole game in miniature.

secret = 12
guess = 10

print("Secret is between 1 and 20.")
print("Guess:", guess)
if guess < secret:
    print("Too low.")
elif guess > secret:
    print("Too high.")
else:
    print("Correct.")

Change guess to 15, then to 12. You should see too high, then correct. That is the hint table the rest of the program will print on every attempt.

Drive the game from a list

In a terminal you would call input() inside a loop. In the browser editor, a stuck prompt is a bad demo. Put the guesses in a list and loop over them. Count every pass. Stop with break when the secret is found.

secret = 12
guesses = [10, 15, 12]
attempts = 0

for guess in guesses:
    attempts += 1
    print("Attempt", attempts, "->", guess)
    if guess == secret:
        print("Hit.")
        break
    if guess < secret:
        print("Too low.")
    else:
        print("Too high.")

print("Attempts used:", attempts)

Complete program

This is the full game. The secret is 12 so the demo list [10, 15, 12] wins on the third try. Run it at /try. You should see two hints, then a win line with the attempt count.

LOW = 1
HIGH = 20
SECRET = 12
GUESSES = [10, 15, 12]

print("Guess the number.")
print("Range:", LOW, "to", HIGH)

attempts = 0
won = False

for guess in GUESSES:
    attempts += 1
    print()
    print("Attempt", attempts, ":", guess)
    if guess < LOW or guess > HIGH:
        print("Out of range. Stay between", LOW, "and", HIGH, ".")
        continue
    if guess < SECRET:
        print("Too low.")
    elif guess > SECRET:
        print("Too high.")
    else:
        print("Correct! The number was", SECRET)
        won = True
        break

print()
if won:
    print("You won in", attempts, "attempts.")
else:
    print("No more guesses. The number was", SECRET)

The range check is extra, not required for this demo list. It shows how you reject a value without counting it as a win. continue skips the rest of that loop pass and moves to the next guess.

Optional: type guesses with input

After the list version works, you can swap the list for input(). Run this only when you are ready to type. The browser editor will wait until you enter a line.

# Optional interactive variant. The complete program above does not need this.
secret = 12
attempts = 0
while True:
    attempts += 1
    guess = int(input("Guess: "))
    if guess == secret:
        print("Correct in", attempts, "tries.")
        break
    if guess < secret:
        print("Too low.")
    else:
        print("Too high.")

Common mistakes

• Using input() as the only path, then wondering why Run sits still. Demo with a list first.
• Comparing strings to integers. input() returns text. Wrap it with int(...) if you switch to typing.
• Forgetting break. The loop then keeps printing after the player already won.
• Resetting attempts inside the loop. The counter must live outside so it survives each pass.
• Calling random.randint without a seed in a tutorial screenshot. The secret then changes every run and the written guesses no longer match. Fix the secret for demos.

How to extend / Practice tasks

Make three concrete changes. Run after each one.

1. Set SECRET = 7 and change GUESSES to [5, 9, 7]. Confirm the hints flip from too low to too high to correct.
2. Widen the range to 1 through 50. Add a fourth guess that is 51 and check that the out-of-range branch prints.
3. Track the best (lowest) attempt count across two playthroughs in the same file: run the loop twice with two different guess lists and print which list won faster.