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! While you're at it, check out some resources Treehouse students have shared here.

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 JavaScript Numbers The Math Object Random Number Challenge – Two Numbers Solution

Posted by Frank Greek
.a{fill-rule:evenodd;}techdegree
Frank Greek
Full Stack JavaScript Techdegree Student 981 Points

know the difference when the user doesn't type alower number in the dialogue bar and when doesn't type highest number

This is my code: it didn't work for the highest number. Even when I didn't put the number to the highest number it showed me the message "provide numbers to the lowest number"

Thank you for answer

const lowestNumber = prompt("Provide a lowest number");

const highestNumber = prompt("Provide a highest number");

const number2 = (+lowestNumber) const number = (+highestNumber)

if (number && number2){

let RandomNumber = Math.floor(Math.random() * highestNumber + 1)

let message = <h1> ${RandomNumber} </h1> <h2>is a random number between ${lowestNumber} and ${number}</h2>;

document.querySelector("main").innerHTML = message

}else if(lowestNumber !== isNaN){ alert("provide numbers to lowest number")

}else if(highestNumber !== isNaN){ alert("provide numbers to highest number")

}else{

}

1 Answer

Steven Parker
Steven Parker
231,248 Points
Steven Parker
Steven Parker
231,248 Points

When posting code, always use Markdown formatting to preserve the code's appearance, and special characters (like back-tick).

This code is comparing things to isNan as if it were a value. But it is a function, so it should be called with the value to be tested passed as an argument. For example:

} else if (isNaN(lowestNumber)) {

Also, the "+" operator converts strings to numbers differently than parseInt(). In particular, if you use the "+" on an empty string, it returns a 0 instead of a NaN.