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JavaScript

Posted by elpsycongroo
elpsycongroo
2,368 Points

Why does this still work without parseInt?

var randomNumber = getRandomNumber(10);
var guess;
var guessCount = 0;

function getRandomNumber( upper ) {
    var num = Math.floor(Math.random() * upper) + 1; 
    return num;
}

do {
    guess = prompt("Pick a number from 1-10");
    guessCount += 1;
} while(guess != randomNumber);

document.write("<h1>You guessed the number!</h1>");
document.write("It took you " + guessCount + " tries to guess the number");

Shouldn't it have to be while(parseInt(guess) != randomNumber); considering prompt converts the users input to a string?

Thanks!

1 Answer

Christopher Augg
Christopher Augg
21,223 Points

Heya,

It is due to how js uses comparison operators.

3 == "3" is true - this does not test for type comparison (int equals String)

3 === "3" is false - this does test for type

Same goes for != and !==

Check out [W3Schools]https://www.w3schools.com/js/js_comparisons.asp)