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JavaScript

Posted by Erin Vaage
Erin Vaage
4,147 Points

How can I find the sum of an array of numbers in JavaScript?

I need to create a function that takes in an array of numbers an adds them up. I don't know JavaScript that well yet and am trying to do this by either using reduce or possibly by looping over all items. How would you do this?

2 Answers

Oliver Duncan
Oliver Duncan
16,642 Points

JavaScript has a reduce function now (I don't think it was always that way). Try this:

function sum(numbers) {
  return numbers.reduce(function(a,b) {
    return a + b
  });
}

Keep in mind that this function has to take an array of values, otherwise it won't work.

Luke Pettway
Luke Pettway
16,593 Points

Bonus points (if I could for) using reduce!

Erin Vaage
Erin Vaage
4,147 Points
Erin Vaage
Erin Vaage
4,147 Points

Just what I needed! Thanks, Oliver.