Activity 2.7 Rock, Paper, Scissors

Introduction

In this activity, you will use loops and selection statements to create the classic game of Rock, Paper, Scissors. This will be a console-based game, utilizing prompt() to get the player's choice and confirm() to ask if they want to play again.

Objectives

Implementing game logic if statements and loops

Activity Tasks

Create a new project named 2-7-rock-paper.js.
Complete each task individually.

Task 1: Initialize Game Data

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let wins = 0;
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let losses = 0;
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let round = 1;
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let playing = true;
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let player;
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let computer;
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/*
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Rules:
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Rock smashes Scissors
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Paper covers Rock
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Scissors cuts Paper
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*/
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console.log("--- Rock, Paper, Scissors ---")

Task 2: Begin Core Game Loop

Display the round number and Wins/Losses.
User inputs rock, paper, or scissors.
Computer generates a random hand.


15 collapsed lines
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let wins = 0;
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let losses = 0;
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let round = 1;
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let playing = true;
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let player;
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let computer;
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/*
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Rules:
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Rock smashes Scissors
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Paper covers Rock
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Scissors cuts Paper
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*/
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console.log("--- Rock, Paper, Scissors ---")
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while (playing) {
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    console.log("Round " + round);
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    console.log(`W: ${wins} - L: ${losses}\n`);
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    player = prompt("(rock, paper, scissors):").toLowerCase();
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    // Pick computer hand
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    let random = Math.floor(Math.random() * 3); // 0 to 2
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    if (random == 0) {
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        computer = "rock";
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    }
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    else if (random == 1) {
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        computer = "paper";
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    }
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    else {
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        computer = "scissors";
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    }
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    console.log(`Computer chooses ${computer}!`);
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}
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//

Task 3: Implement Win/Loss Conditions

If player and computer pick the same hand: tie.
There are three possible win conditions.
If the player neither ties nor wins, they lose.


15 collapsed lines
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let wins = 0;
2
let losses = 0;
3
let round = 1;
4
let playing = true;
5
let player;
6
let computer;
7

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/*
9
Rules:
10
Rock smashes Scissors
11
Paper covers Rock
12
Scissors cuts Paper
13
*/
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console.log("--- Rock, Paper, Scissors ---")
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while (playing) {
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    console.log("Round " + round);
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    console.log(`W: ${wins} - L: ${losses}\n`);
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    player = prompt("(rock, paper, scissors):").toLowerCase();
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    // Pick computer hand
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    let random = Math.floor(Math.random() * 3); // 0 to 2
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    if (random == 0) {
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        computer = "rock";
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    }
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    else if (random == 1) {
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        computer = "paper";
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    }
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    else {
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        computer = "scissors";
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    }
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    console.log(`Computer chooses ${computer}!`);
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    // Regarding the win condition:
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    // It's okay to break a condition over multiple lines if it get too long.
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    if (player == computer) {
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        console.log("-TIE-");
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    }
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    else if (
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        (player == "rock" && computer == "scissors") ||
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        (player == "paper" && computer == "rock") ||
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        (player == "scissors" && computer == "paper")
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    ) {
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        console.log("-YOU WIN-");
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        wins++;
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    }
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    else {
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        console.log("-YOU LOSE-");
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        losses++;
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    }
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    round++;
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    // confirm() returns true or false depending on the answer
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    playing = confirm("Play again?");
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}
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//

Task 4: Show Final Score


60 collapsed lines
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let wins = 0;
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let losses = 0;
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let round = 1;
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let playing = true;
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let player;
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let computer;
7

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/*
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Rules:
10
Rock smashes Scissors
11
Paper covers Rock
12
Scissors cuts Paper
13
*/
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console.log("--- Rock, Paper, Scissors ---")
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while (playing) {
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    console.log("Round " + round);
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    console.log(`W: ${wins} - L: ${losses}\n`);
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    player = prompt("(rock, paper, scissors):").toLowerCase();
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    // Pick computer hand
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    let random = Math.floor(Math.random() * 3); // 0 to 2
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    if (random == 0) {
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        computer = "rock";
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    }
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    else if (random == 1) {
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        computer = "paper";
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    }
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    else {
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        computer = "scissors";
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    }
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    console.log(`Computer chooses ${computer}!`);
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    // Regarding the win condition:
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    // It's okay to break a condition over multiple lines if it get too long.
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    if (player == computer) {
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        console.log("-TIE-");
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    }
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    else if (
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        (player == "rock" && computer == "scissors") ||
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        (player == "paper" && computer == "rock") ||
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        (player == "scissors" && computer == "paper")
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    ) {
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        console.log("-YOU WIN-");
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        wins++;
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    }
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    else {
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        console.log("-YOU LOSE-");
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        losses++;
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    }
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    round++;
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    // confirm() returns true or false depending on the answer
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    playing = confirm("Play again?");
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}
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console.log("\n--- Final Score ---");
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console.log(`Wins: ${wins} - Losses: ${losses}`);
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console.log("Thanks for playing!");
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//

Sample Output

Your program output should something similar to the sample output below.

--- Rock, Paper, Scissors ---
Round 1
W: 0 - L: 0

(rock, paper, scissors): rock
Computer chooses scissors!
-YOU WIN-
Play again? [y/N] y
Round 2
W: 1 - L: 0

(rock, paper, scissors): paper
Computer chooses paper!
-TIE-
Play again? [y/N] y
Round 3
W: 1 - L: 0

(rock, paper, scissors): scissors
Computer chooses rock!
-YOU LOSE-
Play again? [y/N] n

--- Final Score ---
Wins: 1 - Losses: 1
Thanks for playing!

Reflection Questions

You may write your reflection answers as comments at the bottom of your code.

If you wanted to play best-of-5 instead of a continuous game, how would you change the while loop condition?

Submission

Submit your activity and reflection answers to the appropriate dropbox.