Help With Function's Random Outcome

Help With Function's Random Outcome


Hello all, I’ve been working on a Rock, Paper, Scissors game and although it works I cannot get the results to change. I always ‘throw’ rock and the computer always ‘throws’ scissors unless I manually change the switch parameters. I’m looking to get the outcome to be random each time.

Below is my code, although I am NOT looking for anyone to just give me the answer. If you can point me in the right direction(s) that would be awesome :rofl: Any and all help is greatly appreciated! Have a great day and happy coding!

const getUserChoice = (userInput) => {
  userInput = userInput.toLowerCase();
  if (userInput === "rock" || userInput === "paper" || userInput === "scissor"){
    return userInput;
  } else {

const getComputerChoice = () => {
  Math.floor(Math.random() * 1);
  switch (1) {
    case 0:
      return 'rock';
    case 1:
      return 'paper';
    case 2: 
      return 'scissors';

const determineWinner = (userChoice, computerChoice) => {
  if (userChoice === computerChoice) {
    return "It's a tie!";

if (userChoice === 'rock') {
  if (computerChoice === 'scissors')
    return "You win!";
	} else {
  return "You lose!";

if (userChoice === 'paper') {
  if (computerChoice === 'rock');
  	return "You lose!";
	} else {
    return "You win!";

if (userChoice === 'scissors') {
  if (computerChoice === 'paper');
  return "You win!";
} else {
  return "You lose!";

playGame = () => {
  var userChoice = getUserChoice('rock');
  var computerChoice = getComputerChoice();
  console.log('You threw ' + userChoice);
  console.log('The computer threw ' + computerChoice);
  console.log(determineWinner(userChoice, computerChoice)) 



The problem is with your switch statement, you need to make the switch condition a variable, right now it is a constant

Edit: also I would add that you review how Math.random() works , while remembering that it only generates random numbers from 0 to 1 (0 inclusive, but not including 1)


Much thanks for all your help, I hadn’t even looked at that. So basically set the condition to a variable (randomNumber)?

I appreciate the feedback about Math.random() as well!


Use this pattern:

const anyOf = xs => xs[Math.floor(Math.random() * xs.length)]

const foo = anyOf(['rock', 'paper', 'scissors']) // each time returns random array element


Yes, but not any randomNumber, but one that is within the range of choices that the computer should return, which in your case would be 3 choices. You are already on the correct path with this statement:
Math.floor(Math.random() * 1)

However, you can’t use it as is because, as I said before, Math.random() returns numbers between 0 to 1 , with the minimum being 0 and the maximum being 0.99999… while Math.floor() always returns the largest integer less than or equal to a given real number, therefore the statement above will always return 0.

So, figure out what to multiply Math.random() with before applying Math.floor() and you should be good to go.


@0Prime - When a camper asks not to just give him/her the answer, see if you can present your response as a learning opportunity by given hints and references, so the camper can work out the solution on their own.