This article will share some solutions to get the sum of all numbers in a Set using JavaScript. Let’s get started.
How to get the sum of all numbers in a Set
The Set objects are collections of values. A value in the Set may only occur once. You can iterate through the elements of the Set object in insertion order.
To get the sum of all numbers in a Set, we need to create a let
variable representing the sum of the numbers in the Set. Declaring the let
variable allows us to update the value of the variable.
Because the Set object has the properties of an array, we can use the forEach()
method to call a function on each element of the Set.
The complete code to get the sum of all numbers in a Set using the forEach()
method is as follows:
// Create a Set object const setObj = new Set([5, 4, 3, 2, 1]); console.log(setObj); let sum = 0; // Get the sum of all numbers in a Set using the forEach() method setObj.forEach((number) => { sum += number; }); console.log("The sum of all numbers in the 'setObj' Set"); console.log(sum);
Output:
Set(5) { 5, 4, 3, 2, 1 }
The sum of all numbers in the 'setObj' Set
15
Another solution to get the sum of all numbers in a Set is to use the reduce()
method.
The reduce()
method is used to reduce the values of an array to a single value. This method executes a function for each array element (from left to right) and does not mutate the original array.
Syntax:
array.reduce(function(), initialValue)
Parameters:
function(): a function to be executed for each element.
initialValue: the initial value.
However, the reduce()
method only works on array objects. If you want to use this method on a Set object, you must convert this Set object to an array object using the Array.from()
method.
Example:
// Create a Set object const setObj = new Set([5, 4, 3, 2, 1]); console.log(setObj); // Convert the 'setObj' Set object to an array object const setArray = Array.from(setObj); // Get the sum of all numbers in a Set using the reduce() method function getSum(sum, number) { return sum + number; } const sum = setArray.reduce(getSum, 0); console.log("The sum of all numbers in the 'setObj' Set"); console.log(sum);
Output:
Set(5) { 5, 4, 3, 2, 1 }
The sum of all numbers in the 'setObj' Set
15
Summary
This article shared two solutions to get the sum of all numbers in a Set using JavaScript. If you use reduce()
method, remember to convert the Set object to an array object. If you use the forEach()
method, declare the variable that stores the sum as a let
variable so that we can update the variable’s value. Thank you for reading.

Hello, my name’s Bruce Warren. You can call me Bruce. I’m interested in programming languages, so I am here to share my knowledge of programming languages with you, especially knowledge of C, C++, Java, JS, PHP.
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Programming Languages: C, C++, Java, JS, PHP