sum up all numbers of array code example

Example 1: sum of all numbers in an array javascript

const arrSum = arr => arr.reduce((a,b) => a + b, 0)

Example 2: how to add up all numbers in an array

var numbers = [10, 20, 30, 40] 
var sum = 0;
for (var i = 0; i < numbers.length; i++) {  sum += numbers[i]}