app.py

import random

def main():
    print("Let's play Rock, Paper, Scissors!")
    print("Enter your choice (1 for Rock, 2 for Paper, 3 for Scissors): ")
    
    try:
        user_choice = int(input("Your choice: "))
    except ValueError:
        print("Invalid input! Please enter a number between 1 and 3.")
        return

    if user_choice not in [1, 2, 3]:
        print("Invalid choice! Please enter 1, 2, or 3.")
        return

    computer_choice = random.randint(1, 3)

    choices = {1: "Rock", 2: "Paper", 3: "Scissors"}
    print(f"Computer chose: {choices[computer_choice]}")

    if user_choice == computer_choice:
        print("It's a tie!")
    elif (user_choice == 1 and computer_choice == 3) or \
         (user_choice == 2 and computer_choice == 1) or \
         (user_choice == 3 and computer_choice == 2):
        print("You win!")
    else:
        print("Computer wins!")

if __name__ == "__main__":
    main()