JavaScript: Issue with numerical condition in if statement

Other Questions JavaScript
1 
I'm having trouble with my code. It stops working at this line:

if (value1 < 4000000 && value.isInteger(value1/2))

Here's my function:

function fibonacciSum() {
  let value1 = 1;
  let value2 = 2;
  let total = 0;

  while (value1 && value2 < 4000000) {
    if (value1 < 4000000 && value.isInteger(value1/2)) {
      total += value1;
    }
    if (value2 < 4000000 && value.isInteger(value2/2)) {
      total += value2;
    }
    value1 = value1 + value2;
    value2 = value1 + value2;
  }
  alert(total);
}

fibonacciSum();

Can anyone spot the issue? The program doesn’t run past the first if statement inside the while loop. I’m trying to sum up even Fibonacci numbers below 4 million. Thanks for any help!

2

I’ve encountered similar issues before, and I think I see the problem in your code. The main issue is with the value.isInteger() method. In JavaScript, isInteger() is a method of the Number object, not value. You should use Number.isInteger() instead.

Also, your while loop condition isn’t quite right. You’re checking if both values are less than 4 million, but you only need one to be. Here’s how I’d modify your function:

function fibonacciSum() {
  let value1 = 1;
  let value2 = 2;
  let total = 0;

  while (value1 < 4000000) {
    if (value1 % 2 === 0) {
      total += value1;
    }
    let temp = value1 + value2;
    value1 = value2;
    value2 = temp;
  }
  alert(total);
}

This should work correctly. I’ve simplified the even number check to value1 % 2 === 0, which is more efficient. Hope this helps!

3

hey mate, i think i kno whats goin on. ur using value.isInteger() which aint a thing in js. try Number.isInteger() or just do value1 % 2 === 0 to check for even nums. also ur while loop looks funky. mayb try while (value1 < 4000000) instead. hope that helps!

4

I see the issue in your code. The problem lies in the value.isInteger() method. JavaScript doesn’t have this method on regular numbers. Instead, you should use Number.isInteger() or a simpler approach like checking if the remainder is zero when divided by 2.

Here’s a corrected version of your function:

function fibonacciSum() {
  let value1 = 1;
  let value2 = 2;
  let total = 0;

  while (value1 < 4000000) {
    if (value1 % 2 === 0) {
      total += value1;
    }
    let temp = value1 + value2;
    value1 = value2;
    value2 = temp;
  }
  alert(total);
}

This should work as intended. The while loop condition has been simplified, and the even number check is now more straightforward. Give it a try and let us know if you have any other questions.