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JavaScript JavaScript Basics (Retired) Working With Numbers The Random Challenge

Glen Segers
Glen Segers
1,223 Points

my take on the challenge, feel free to give some input

// random number between 1 and user selected

var num = prompt("pick your number"); var random = Math.floor(Math.random()*parseInt(num)) +1; alert("The random number is " + random);

// random number between 2 user selected numbers

var num = prompt("pick your lowest number"); var num2 = prompt("pick your highest number"); var random = Math.floor(Math.random()*parseInt(num2 - num)) +parseInt(num); alert("The random number is " + random);

Matthew Lanin
seal-mask
.a{fill-rule:evenodd;}techdegree
Matthew Lanin
Full Stack JavaScript Techdegree Student 8,003 Points

Just fyi, if you hit the "Markdown Cheatsheet" link when making a post, it will show you how to format your code to make it easier to read on here, like this.

// random number between 1 and user selected
var num = prompt("pick your number"); 
var random = Math.floor(Math.random() * parseInt(num)) +1; 
alert("The random number is " + random);

// random number between 2 user selected numbers

var num = prompt("pick your lowest number"); 
var num2 = prompt("pick your highest number"); 
var random = Math.floor(Math.random() * parseInt(num2 - num)) + parseInt(num); 
alert("The random number is " + random);

But your work looks good to me, running well when I try it.

Glen Segers
Glen Segers
1,223 Points

thank you both for the input, ill kepe it in mind. was my first try from scratch and uploading it

Steven Parker
Steven Parker
229,982 Points

Use the instructions for code formatting in the Markdown Cheatsheet pop-up below the "Add an Answer" area. :arrow_heading_down:
Or watch this video on code formatting.

1 Answer

Steven Parker
Steven Parker
229,982 Points

You can't perform subtraction on string inputs before converting them into a number, but it may seem to work because of implicit type conversion. You'll need to convert each one individually and then you can subtract them.
:x: parseInt(num2 - num)
:white_check_mark: parseInt(num2) - parseInt(num)

And rather than performing a conversion multiple times on the same string, you could convert it just once and assign the result to a new variable. Then use that variable as many times as needed.

Also, in both cases your random numbers may include the low limit (1 or the user input), but will not include the high limit. If you wish to include the high limit, add one to the number you multiply by.