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

Posted by Sebastian Akerman
Sebastian Akerman
1,572 Points

So what if the lowNumber entered is higher than the highNumber? How do we adjust this in our code?

This would result in the following console.log statement

Ie) 5 is a number between 1 and 1.

How do we correct this to add a message like "Your low number is higher than your high number, please adjust and try again"...? Thanks for helping :D

Raynauld Minkema
Raynauld Minkema
12,832 Points
Raynauld Minkema
Raynauld Minkema
12,832 Points

I used this:

if (inputNumberLow >= inputNumberHigh) { console.log('Your second number is not higher than the first! Error!');

Which is probably a bit crude, but it worked for me.

Jason Rich
seal-mask
.a{fill-rule:evenodd;}techdegree
Jason Rich
Front End Web Development Techdegree Student 10,048 Points
Jason Rich
.a{fill-rule:evenodd;}techdegree
Jason Rich
Front End Web Development Techdegree Student 10,048 Points

Here's how I made that check.

const userNumber1 = prompt(`Can I get a number please?`);
const userNumber2 = prompt(`And a second, larger number?`);

const lowNumber = parseInt(userNumber1);
const highNumber = parseInt(userNumber2);

if (lowNumber < highNumber) {
    const random = Math.floor(Math.random() * (highNumber - lowNumber + 1) + lowNumber);
    console.log(`${random} is a random number between ${lowNumber} and ${highNumber}.`);
} else if (lowNumber > highNumber) {
    console.log(`Please provide a larger second number. Try again.`);
} else {
    console.log(`Please provide a number. Try again.`)
}

1 Answer

Sean Do
Sean Do
11,933 Points
Sean Do
Sean Do
11,933 Points

You could give an error to the user stating the first number needs to be lower than the second number, but I think that would be a bad user experience to force reload. What I did to check after you've validated both numbers are numbers, I do a check between the two numbers which is higher than the other. Then I put the variables according to their equation. Of course, a function is a more advanced topic, but I figured to use it since I was repeating code. 

// Collect input from a user
const inputLow = prompt("Please enter a number: ");
const inputHigh = prompt("Please enter another number: ");

function getRandomInt(min, max) {
  min = Math.ceil(min);
  max = Math.floor(max);
  return Math.floor(Math.random() * (max - min + 1));
}
// Convert the input to a number
const lowNumber = parseInt(inputLow);
const highNumber = parseInt(inputHigh);

// Checks
if (lowNumber || highNumber) {
  if (lowNumber > highNumber) {
    console.log(getRandomInt(highNumber, lowNumber) + ` is a random number between ${highNumber} and ${lowNumber}`);
  } else {
    console.log(getRandomInt(lowNumber, highNumber) + ` is a random number between ${lowNumber} and ${highNumber}`);    
  }
} else {
  console.log("You need to provide a number. Try again.");
}