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JavaScript: Sum of the digits of a number

JavaScript Math: Exercise-68 with Solution

Write a JavaScript program to calculate the sum of a given number's digits.

In mathematics, the digit sum of a natural number in a given number base is the sum of all its digits. For example, the digit sum of the decimal number 6098 would be 6+0+9+8=23.

Sample Data:
6098 -> 23
-501 -> 6
2546 -> 17

Sample Solution-1:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript function to sum of the digits of a number</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function sum_Of_Digits(n) {
  if (n < 0) n = -n
  let result = 0

  while (n > 0) 
   {
    result += n % 10
    n = Math.floor(n / 10)
  }

  return result
}
console.log(sum_Of_Digits(6098))
console.log(sum_Of_Digits(-501))
console.log(sum_Of_Digits(2546))

Sample Output:

23
6
17

Flowchart:

JavaScript Math flowchart of sum of the digits of a number

Live Demo:

See the Pen javascript-math-exercise-68 by w3resource (@w3resource) on CodePen.


Sample Solution-2:

JavaScript Code:

function sum_Of_Digits(n) {
  if (n < 0) n = -n
   if (n < 10) return n
   return (n % 10) + sum_Of_Digits(Math.floor(n / 10))
}
console.log(sum_Of_Digits(6098))
console.log(sum_Of_Digits(-501))
console.log(sum_Of_Digits(2546))
console.log(sum_Of_Digits(10))
console.log(sum_Of_Digits(5))

Sample Output:

23
6
17
1
5

Flowchart:

JavaScript Math flowchart of sum of the digits of a number

Live Demo:

See the Pen javascript-math-exercise-68-1 by w3resource (@w3resource) on CodePen.


Improve this sample solution and post your code through Disqus

Previous: Sum of a geometric progression.
Next: Find all prime numbers below a given number.

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JavaScript: Tips of the Day

Randomizes the order of the values of an array, returning a new array

Example:

const tips_shuffle = ([...arr]) => {
  let x = arr.length;
  while (x) {
    const i = Math.floor(Math.random() * x--);
    [arr[x], arr[i]] = [arr[i], arr[x]];
  }
  return arr;
};
const foo = [2, 4, 6];
console.log(tips_shuffle(foo));

Output:

[4, 2, 6]

 

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