How to useArray Reduce() Method in Javascript
In this approach, the reduce method transforms each digit of a number into an accumulated sum. It converts the number to a string, iterates, and adds each digit to the sum.
Syntax:
array.reduce( function(total, currentValue, currentIndex, arr), initialValue )
Example: In this example, the sumOfDigit function converts the number to a string, splits it into digits, and then reduces by adding parsed digits, resulting in the sum.
function sumOfDigit(num) {
return num.toString().split("")
.reduce((sum, digit) =>
sum + parseInt(digit), 0);
}
console.log(sumOfDigit(738));
Output
18
JavaScript Program for Sum of Digits of a Number
In this article, we are going to learn about finding the Sum of Digits of a number using JavaScript. The Sum of Digits refers to the result obtained by adding up all the individual numerical digits within a given integer. It’s a basic arithmetic operation. This process is repeated until a single-digit sum, also known as the digital root.
There are several methods that can be used to find the Sum Of Digits by using JavaScript, which are listed below:
Table of Content
- Approach 1: Using Array Reduce() Method
- Approach 2: Using For…of Loop
- Approach 3: Using Math.floor and Division
- Approach 4: Using forEach
- Approach 5: Using Recursion
We will explore all the above methods along with their basic implementation with the help of examples.