w3resource

JavaScript: Calculate the sum of n + n/2 + n/4 + n/8 + ....

JavaScript Basic: Exercise-113 with Solution

Write a JavaScript program to calculate the sum of n + n/2 + n/4 + n/8 + .... where n is a positive integer and all divisions are integer.

Pictorial Presentation:

JavaScript: Calculate the sum of n + n/2 + n/4 + n/8 + .....

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title> Calculate the sum of n + n/2 + n/4 + n/8 + ....</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function int_sum(num) {
    var s_sum = 0;
    while (num > 0) {
        s_sum += num;
        num = Math.floor(num / 2);
    }
    return s_sum;
}
console.log(int_sum(8))
console.log(int_sum(9))
console.log(int_sum(26))

Sample Output:

15
16
49

Flowchart:

Flowchart: JavaScript - Calculate the sum of n + n/2 + n/4 + n/8 + ....

ES6 Version:

function int_sum(num) {
    let s_sum = 0;
    while (num > 0) {
        s_sum += num;
        num = Math.floor(num / 2);
    }
    return s_sum;
}
console.log(int_sum(8))
console.log(int_sum(9))
console.log(int_sum(26))

Live Demo:

See the Pen javascript-basic-exercise-113 by w3resource (@w3resource) on CodePen.


Contribute your code and comments through Disqus.

Previous: Write a JavaScript program to find the number of trailing zeros in the decimal representation of the factorial of a given number.
Next: Write a JavaScript program to check whether a given string represents a correct sentence or not.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Share this Tutorial / Exercise on : Facebook and Twitter

JavaScript: Tips of the Day

Checks if a string is an anagram of another string (case-insensitive, ignores spaces, punctuation and special characters)

Example:

const isAnagram = (str1, str2) => {
  const normalize = str =>
    str
      .toLowerCase()
      .replace(/[^a-z0-9]/gi, '')
      .split('')
      .sort()
      .join('');
  return normalize(str1) === normalize(str2);
};
console.log(isAnagram('iceman', 'cinema')); // true

Output:

true