How to sum an array of numbers using reduce()
Swift version: 5.0
The reduce() method is designed to convert a sequence into a single value, which makes it perfect for calculating the total of an array of numbers.
For example, given the following number array:
let numbers = [1, 12, 2, 9, 27]We could calculate the total of all those numbers like this:
let total = numbers.reduce(0, +)The first parameter passed to reduce() is the value it should start with, in this case 0. The second parameter is how it should combine that 0 with each item in your array, which means it will do 0 + 1 to make 1, then 1 + 12 to make 13, and so on.
HACKING WITH SWIFT LIVE This July is a new two-day event where you'll be inspired by great speakers on day one then learn all the amazing new features from WWDC on day two – click here for more information and tickets.
Available from iOS 8.0
Did this solution work for you? Please pass it on!
Other people are reading…
- How to use ISO-8601 dates with JSONDecoder and Codable
- How to filter a loop using a where clause
- What is the @objc attribute?
- How to find the maximum of three numbers
- How to remove the first or last item from an array
About the Swift Knowledge Base
This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.
