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Discussion on: JavaScript beginner help

 
alvaromontoro profile image
Alvaro Montoro

You want to know the number of numbers that are divisible by k and are between n and m, right?

Why are you doing this result = result / i;?

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roxor profile image
roxor • Edited

correct

hm, I try the divisible result. but now, when I better think about it that is stupid

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alvaromontoro profile image
Alvaro Montoro

It's not stupid. It is just not what you need.

So, inside that if you have verified that the number is divisible, you don't really need to do more operations with it. Just have a counter –you could use result– to track how many there are. You could do something like result++; instead.

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roxor profile image
roxor • Edited

I try is not working

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alvaromontoro profile image
Alvaro Montoro

Hmmmm... What did you end up doing? and what result are you expecting? I do divisible(1,10,3) and get 3 which is correct (because 3, 6, and 9 and divisible by 3).

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roxor profile image
roxor • Edited

my console looks like this

Can you show me how u write a code?

ƒ divisible(n, m, k){
result = 1;
for (i = n; i <= m; i++) {
if (i % k == 0) {
result ++
}
}
console.log(divisible);
}
divisible(1, 10, 3)

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roxor profile image
roxor

I do exactly like you, in console this ƒ show up

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alvaromontoro profile image
Alvaro Montoro • Edited

The console.log should be with result. You are printing the wrong variable ;)

+result should be initialized to 0 instead of 1, but apart from that, you are one :)

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roxor profile image
roxor

oh man, now is working...

I start with 1 cuz when we do addition we start from 0, when we multiply we start from 1

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alvaromontoro profile image
Alvaro Montoro

Nice. So you got everything working?

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roxor profile image
roxor

yes, and the last one is number two. I don't have clue how to do this

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alvaromontoro profile image
Alvaro Montoro

For the second one you have to write a function that gets a number as a parameter that represents a year, and returns the age of the person. For that one you'll need to use the Date object (and the getFullYear() method) to get the current year and calculate the difference of the two.

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roxor profile image
roxor • Edited

let day = new Date();
let birthday = day.getFullYear;
function birh(n){
let calculate = day.getFullYear - n;
return(calculate)
}

console.log(n);

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roxor profile image
roxor

something like this?

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alvaromontoro profile image
Alvaro Montoro

Those are steps in the right direction. But take into account some things:

  • You should have the variables in the scope of the function (right now you are defining the variables globally)
  • The method getFullYear() is part of Date. Considering that you are doing let day = new Date() then you'd need to do day.getFullYear() to get the current year.
  • In the console.log, you should return the result of the function and not the value that you pass to it.

With those changes, the code would look like this:

function birth(n){
  let day = new Date();
  let day1 = day.getFullYear();
  let calculate = day1 - n;
  return(calculate)
}

let n = 2000;
console.log(birth(n));

One of the things that you should do too is having descriptive names for variables. Right now you are storing dates in day, the year in day1, the birth year in n... That will be helpful in the future to maintain the code and help debug it.

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roxor profile image
roxor

Understood, in case if u want to call in another function day.getFullYear must make new, cuz this is work only in block of function birth, right?

Thank you for advice, I must try do give more descriptive names for var.

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alvaromontoro profile image
Alvaro Montoro

The variables will only work in the function/block where they were defined. So if you want to use it somewhere else, you'll need to redefine it or make it global.

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roxor profile image
roxor • Edited

I get it, thank you for the explanation you help me a lot.
When I get a job, from my first paycheck I will buy you a coffee.

thank you one more time. Cheers!