How to calculate division remainder using modulo

Paul Hudson    February 19th 2018    @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")
    }
}

Available from iOS 8.0

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