Building a Rock-Paper-Scissors Game in Python

Why I studied this

I wanted to build a simple game using Python to practice conditionals, loops, and random values.
By creating a rock-paper-scissors game, I could practice using functions, store game data, and track results over time.

---

What I did

1. Function to decide the winner

def isWinner(computer, person):
    if computer == person:
        return 3  # draw

    if (computer == 1 and person == 3) or        (computer == 2 and person == 1) or        (computer == 3 and person == 2):
        return 1  # computer wins

    return 2  # player wins

This function takes two numbers (1 = Scissors, 2 = Rock, 3 = Paper) and returns the result:

• 1: Computer wins
• 2: Player wins
• 3: Draw

---

2. Game engine: 10 rounds with random choices

import random

titles = ["", "Scissors", "Rock", "Paper"]
titles2 = ["", "Computer wins", "Player wins", "Draw"]
gameList = []

def gameStart():
    gameList.clear()
    for i in range(10):
        computer = random.randint(1, 3)
        person = random.randint(1, 3)
        winner = isWinner(computer, person)

        game = {
            "computer": computer,
            "person": person,
            "winner": winner
        }
        gameList.append(game)

        print(f"Computer: {titles[computer]} | Player: {titles[person]} --> {titles2[winner]}")

Each round randomly selects values for the computer and player.
Results are stored in gameList for later review.

---

3. Summary of results

player_win = sum(1 for game in gameList if game["winner"] == 2)
computer_win = sum(1 for game in gameList if game["winner"] == 1)
draw = sum(1 for game in gameList if game["winner"] == 3)

print(f"Player wins: {player_win}, Computer wins: {computer_win}, Draws: {draw}")

After 10 rounds, the program prints the final summary showing how many times each side won.

---

What I struggled with

At first, I tried solving the comparison part in a very inefficient way.
I used two for loops to compare the positions of items in lists, and inside the second loop I used if to match items.
This ended up running 9 times every round (3x3), and it got messy quickly.

Eventually, I stopped overthinking it.
Instead of nested loops, I directly compared list items at the same index.
It was much simpler and faster.
I realized that sometimes the cleanest way is the most direct one.

---

What I learned

• How to structure a multi-round game using functions and lists
• How to use random.randint() for non-repetitive gameplay
• How to count wins using sum() and conditions
• Most importantly, I learned that simple code is better than complicated logic

---

What I want to do next

I want to let users actually input their choice and see how many games they can win.
Also, maybe keep score over multiple sessions!