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

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")



1 Answer

Steven Parker
Steven Parker
229,606 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.