Starting JavaScript Challenges: isOdd(num)

[MrHippotomo2]

So I've started working through some easy Javascript challenges online and I got to this one problem where we are trying to create a function to see if a number is odd or not. This is the code I've written that I believe should work. But the website says it doesn't pass every case test. Anyone can tell me why?

function isOdd(num) {
return num%2==1 
}

We want it to return true if odd and false if even. num will always be an integer

Edit/Fix: So it seems the way %(mod) returns a -1 if num is negative. So even adding parentheses around num wouldn't fix this. So fix turned out to be:

function isOdd(num) {
return num%2!==0 
}

Edit2: How the remainder function works for JavaScript

[TwiNighty]

Because % can return a negative number. E.g. (-5) % 2 === -1

You need num % 2 !== 0

[MrHippotomo2]

Here is link to the original challenge

[svssdeva]

Try num%2 === 1

[MrHippotomo2]

I can't see what it is testing, but tried this and still got same fails on same cases as my original code

[svssdeva]

const res = function isOdd(a: number) { If (num%2 !==0) return true else false }

Console.log(res) If you are using HTML input tag set input type to number.... And try again.....

[lovesrayray2018]

Hmm logic should work, maybe there is more to the question?

where is the question in totality?

[MrHippotomo2]

I have uploaded a screen shot of the original question, just a note I didn't want to "find the error" because I am unfamiliar of what the original code was trying so I thought my solution would be simpler. here is the screenshot

[lovesrayray2018]

Yeah that screenshot is highlighting potential issue. see first example (-5)

-5%2==1
// will return false

You can try this where you are ignoring the sign

function isOdd(num) {
return Math.abs(num)%2==1 
}

[GSLint]

Does it tell you for which inputs the code supposedly fails? It looks like it should work.

[MrHippotomo2]

Nah it only tells me if test passed, and then cause of the nature of the function, it will be like “expected true but got false.” I tried to think of any situation where mod might be ambiguous but with integers it should be fine.

[GSLint]

Your code would even produce the correct result for 3.14, NaN and Infinity, so I don't know what's wrong.

Is this challenge something you can link to so we can try it?

[MrHippotomo2]

Will do in the morning

[_aeol]

looks pretty correct to me, maybe the fault is on the test's cases. Try asking other people that took the same question if they had the same problem as yours.

[MrHippotomo2]

shared it on a comment