sum array element in javascript code example

Example 1: array sum javascript

const arr = [1, 2, 3, 4];
const sum = arr.reduce((a, b) => a + b, 0);
// sum = 10

Example 2: sum of an array

const sum = (...args) => args.reduce((a, b) => a + b, 0);
console.log(sum(1,2,3)); // returns 6