How to get the previous and next elements of an array loop in JavaScript?

Question

In a simple array loop of Javacript as

for (var i=0; i         


        

Answer 1

you need reduce; a built sweet function to get previous and next values of array

[0, 1, 2, 3, 4].reduce(function(previousValue, currentValue, currentIndex, array) {
  return previousValue + currentValue;
});