1const arrSum = arr => arr.reduce((a,b) => a + b, 0)

1 function array(arr){
2   var sum = 0;
3   for (var i = 0; i< arr.length; i++){
4    sum += arr[i];
5   }
6   console.log(sum);
7 }
8 array([5, 1, 3, 3])
9