Rock Paper Scissors Javascript (The Odin Project)-CodePudding

Hello everyone this is my first question here so sorry if it doesn't match all the rules. I am trying to make a rock paper scissors game from the Odin Project in javascript, and I'm having problem with the result output because it doesn't display what it should. If computer plays rock for e. and i play rock i should get it's a draw but i get something random all the time. Current code is with prompt() for user input, but I tried putting a fixed string like "paper" and it was the same, I also thought it was because I didn't put toLowerCase() properly so I removed it completely and it's still the same, I would appreciate your help!

function computerPlay() {
  let rps = ["rock", "paper", "scissors"];
  let random = rps[Math.floor(Math.random() * rps.length)];
  return random;
}

console.log(computerPlay());

function playRound(playerSelection, computerSelection) {
  if (playerSelection === computerSelection) {
    return ("It's a draw!");
  } else if ((playerSelection === "rock") && (computerSelection === "scissors")) {
    return ("You win! Rock beats scissors");
  } else if (playerSelection === "rock" && computerSelection === "paper") {
    return ("You lose! Paper beats rock");
  } else if (playerSelection === "paper" && computerSelection === "rock") {
    return ("You win! Paper beats rock");
  } else if (playerSelection === "paper" && computerSelection === "scissors") {
    return ("You lose! Scissors beat paper");
  } else if (playerSelection === "scissors" && computerSelection === "paper") {
    return ("You win! Scissors beat paper");
  } else if (playerSelection === "scissors" && computerSelection === "rock") {
    return ("You lose!Rock beats scissors");
  }

}

let computerSelection = computerPlay();
let playerSelection = prompt("Choose your weapon");
console.log(playRound(playerSelection, computerSelection));

CodePudding user response：

You first console.log the function computerPlay() and that returns a certain value. After that you play the round and calls again the function computerPlay(), this computes the round with another value than you first console.log.

Try this code below

function computerPlay() {
  let rps = ["rock", "paper", "scissors"];
  let random = rps[Math.floor(Math.random() * rps.length)];
  return random;
}


function playRound(playerSelection, computerSelection) {
  if (playerSelection === computerSelection) {
    return ("It's a draw!");
  } else if ((playerSelection === "rock") && (computerSelection === "scissors")) {
    return ("You win! Rock beats scissors");
  } else if (playerSelection === "rock" && computerSelection === "paper") {
    return ("You lose! Paper beats rock");
  } else if (playerSelection === "paper" && computerSelection === "rock") {
    return ("You win! Paper beats rock");
  } else if (playerSelection === "paper" && computerSelection === "scissors") {
    return ("You lose! Scissors beat paper");
  } else if (playerSelection === "scissors" && computerSelection === "paper") {
    return ("You win! Scissors beat paper");
  } else if (playerSelection === "scissors" && computerSelection === "rock") {
    return ("You lose!Rock beats scissors");
  }

}

let computerSelection = computerPlay();
let playerSelection = prompt("Choose your weapon");
console.log(computerSelection)
console.log(playRound(playerSelection, computerSelection));

CodePudding user response：

You can simplify your conditions in this way

const choices = ["Rock", "Paper", "Scissors"]
const computerPlay = () => choices[Math.floor(Math.random() * choices.length)]


function playRound(playerSelection, computerSelection) {
  const difference = (choices.length   choices.indexOf(playerSelection) - choices.indexOf(computerSelection) )% choices.length
  switch(difference){
   case 0:
       return "It's a draw!"
    case 2:
       return `You lose! ${computerSelection} beats ${playerSelection}`
    default:
       return `You win! ${playerSelection} beats ${computerSelection}`
  }
 
}

let computerSelection = computerPlay();
let playerSelection
while(!choices.includes(playerSelection)){
  const selected = prompt("Choose your weapon").trim().toLowerCase();
  
  playerSelection = selected[0].toUpperCase() selected.slice(1)
 
}
console.log(playRound(playerSelection, computerSelection));