Answers for "using sum in js"

array sum javascript

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

sum values in array javascript

const num = [1, 3, 1, 1] 
const reducer = (accumulator, currentValue) => accumulator + currentValue;
const sum = num.reduce(reducer);
console.log(sum)
// (1+3+1+1) = 6