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iOS Swift Basics Swift Operators Working With Operators

Posted by Brian Bellini
Brian Bellini
3,930 Points

Getting an error line of code in challenge and in Xcode using % operator.

Line of code is:

let result: Double = value % divisor

Xcode says: " % is unavailable: Use truncatingRemainder instead" Challenge says: "Make sure result is assigned result of operation not simply assigned an Int value.

operators.swift 
// Enter your code below
let value: Double = 200
let divisor: Double = 5

let someOperation = 20 + 400 % 10 / 2 - 15
let anotherOperation = 52 * 27 % 200 / 2 + 5

// Task 1 - Enter your code below
let result: Double = value % divisor

// Task 2 - Enter your code below
let isPerfectMultiple: Bool = result == 0

1 Answer

Paul Jackson
Paul Jackson
7,585 Points

Hi Brian,

That error occurs because an expression using the %(modulo) operator returns an integer and in your answer value and divisor are defined as type Double. Swift is telling you to use the truncatingRemainder function because you will lose precision going from Double to Int. To fix the issue simply remove the type Double or change the type to Int for value and ** divisor** and it should work fine.

let value = 200
let divisor = 5

Hope this helps. ?

Brian Bellini
Brian Bellini
3,930 Points

Thanks.