Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community!

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript

Posted by Jaynesh Khatri
Jaynesh Khatri
398 Points

I'm making a Rock Paper Scissors experiment in JavaScript. I don't know what I'm doing wrong. Please Help. The code

console.log("Video Game");

var playerOne = prompt("Player One R=Rock P=Paper S=Scissors");
var playerTwo = prompt("Player Two R=Rock P=Paper S=Scissors");


//Combinations for Ties

if ((playerOne = "r"||"R") && (playerTwo = "r"||"R")) {

    console.log("Tie");
}

else if ((playerOne = "p"||"P") && (playerTwo = "p"||"P")) {

    console.log("Tie");
}

else if ((playerOne = "s"||"S") && (playerTwo = "s"||"S")) {

    console.log("Tie");
}

//Different Combinations to victory

else if ((playerOne = "r"||"R") && (playerTwo = "s"||"S")) {

    console.log("Player One Wins!!!!");
}


else if ((playerOne = "s"||"S") && (playerTwo = "r"||"R")) {

    console.log("Player Two Wins!!!!");
}


else if ((playerOne = "P"||"p") && (playerTwo = "r"||"R")) {

    console.log("Player One Wins!!!!");
}

else if ((playerOne = "r"||"R") && (playerTwo = "p"||"P")){

    console.log("Player Two Wins");
}

else if ((playerOne = "s"||"S") && (playerTwo = "p"||"P")){

    console.log("Player One Wins!!!!");
}

else if ((playerOne = "P"||"p") && (playerTwo = "s"||"S")){

    console.log("Player Two Wins!!!!");
}

2 Answers

Dave McFarland
STAFF
Dave McFarland
Treehouse Teacher
Dave McFarland
Dave McFarland
Treehouse Teacher

HI Jaynesh Khatri

This won't work:

playerOne = "r"||"R"

That code doesn't test the value of the input, it assigns a new value to the playerOne variable. To test to if the player typed 'r' or 'R' you need to use the === operator and you need to use the || operator between 2 different conditions, like this:

playerOne==='r' || playerOne==='R'

Or even better:

playerOne.toUpperCase() === 'R'
Iago Wandalsen Prates
Iago Wandalsen Prates
21,699 Points
Iago Wandalsen Prates
Iago Wandalsen Prates
21,699 Points

It is a valid javascript code, it just doesn't do what he wants.

playerOne = 'r' || 'R' will evaluate if 'r' is a truthy value, and as it is, it will assign 'r' to player one.

Dave McFarland
Dave McFarland
Treehouse Teacher
Dave McFarland
Dave McFarland
Treehouse Teacher

Thanks Iago Wandalsen Prates for pointing that out. Yes, it is valid -- in other words it won't generate a syntax error. It's just not correct for what he wants to do. I've updated my response to be more accurate. Thanks!

James Barnett
James Barnett
39,199 Points
James Barnett
James Barnett
39,199 Points

It is a valid javascript code, it just doesn't do what he wants.

Pesky logic bugs

Jaynesh Khatri
Jaynesh Khatri
398 Points

Thanks for the help

Iago Wandalsen Prates
Iago Wandalsen Prates
21,699 Points
Iago Wandalsen Prates
Iago Wandalsen Prates
21,699 Points

Also, some possible improvement you could do: instead checking if both users are rock, and than saying its a tie, you could just check if playerOne is equal to playerTwo, and save two if statements.

Nesting conditionals will make your code more readable, and executing faster. Instead of checking every single time what are both the inputs, you can first check the first input, and inside it, check for one of the possible inputs (draws have been handled already), and if it checks, give that result, else you give the other result.

Other than that, good job on learning JavaScript, its an awesome language.