# AdditiveArithmetic A type with values that support addition and subtraction. ``` protocol AdditiveArithmetic : Equatable ``` ## Overview The `AdditiveArithmetic` protocol provides a suitable basis for additive arithmetic on scalar values, such as integers and floating-point numbers, or vectors. You can write generic methods that operate on any numeric type in the standard library by using the `AdditiveArithmetic` protocol as a generic constraint. The following code declares a method that calculates the total of any sequence with `AdditiveArithmetic` elements. ``` extension Sequence where Element: AdditiveArithmetic { func sum() -> Element { return reduce(.zero, +) } } ``` The `sum()` method is now available on any sequence with values that conform to `AdditiveArithmetic`, whether it is an array of `Double` or a range of `Int`. ``` let arraySum = [1.1, 2.2, 3.3, 4.4, 5.5].sum() // arraySum == 16.5 let rangeSum = (1..<10).sum() // rangeSum == 45 ``` # Conforming to the AdditiveArithmetic Protocol To add `AdditiveArithmetic` protocol conformance to your own custom type, implement the required operators, and provide a static `zero` property. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)