rock paper scissors codeacademy

var compare=function(user,comp){
    if(user===comp){
    return "The result is a tie!";
    }else if(user==="rock"){
        if(comp==="scissors"){
            return "rock wins";
        }else{
            return "paper wins";
        }
    }else if(user==="paper"){
        if(comp==="rock"){
            return "paper wins";
        }else{
            return "scissors wins"
        }
    }else{
        if(comp==="rock"){
            return "rock wins";
        }else{
            return "scissors wins";
        }
    }
};
var userChoice = prompt("Do you choose rock, paper or scissors?");
if (userChoice !=="rock"||userChoice !=="paper"||userChoice !=="scissors"){
    console.log("invalid input");
}
var computerChoice = Math.random();
if (computerChoice < 0.34) {
	computerChoice = "rock";
} else if(computerChoice <= 0.67) {
	computerChoice = "paper";
} else {
	computerChoice = "scissors";
} console.log("Computer: " + computerChoice);

compare(userChoice,computerChoice);