BLACK FRIDAY: Save 50% on all my Swift books and bundles! >>

How to calculate division remainder using modulo

Swift version: 5.10

Paul Hudson    @twostraws   

Swift has a dedicated remainder operator in the form of %, and it’s used to return the remainder after dividing one number wholly into another. For example, 14 % 3 is 2, because you can fit four 3s into 14, and afterwards you have the remainder 2.

The remainder operator is helpful for calculating things like odd and even numbers – if you want alternate rows of your table to be a slightly different color, for example, you might write this:

for i in 1...10 {
    if i % 2 == 0 {
        print("Number is even")
    } else {
        print("Number is odd")
    }
}

You can also use the isMultiple(of:) method, which does more or less the same thing while being more readable:

for i in 1...10 {
    if i.isMultiple(of: 2) {
        print("Number is even")
    } else {
        print("Number is odd")
    }
}
Save 50% in my WWDC sale.

SAVE 50% All our books and bundles are half price for Black Friday, so you can take your Swift knowledge further without spending big! Get the Swift Power Pack to build your iOS career faster, get the Swift Platform Pack to builds apps for macOS, watchOS, and beyond, or get the Swift Plus Pack to learn advanced design patterns, testing skills, and more.

Save 50% on all our books and bundles!

Available from iOS 8.0

Similar solutions…

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.

BUY OUR BOOKS
Buy Pro Swift Buy Pro SwiftUI Buy Swift Design Patterns Buy Testing Swift Buy Hacking with iOS Buy Swift Coding Challenges Buy Swift on Sundays Volume One Buy Server-Side Swift Buy Advanced iOS Volume One Buy Advanced iOS Volume Two Buy Advanced iOS Volume Three Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with macOS Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let us know!

Average rating: 4.6/5

 
Unknown user

You are not logged in

Log in or create account
 

Link copied to your pasteboard.