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# My code doesn't pass the challenge. It works in my own playground.

higherOrderFunctions.swift
/**
For this code challenge, letβs define a math operation as a function that
carries out some work on two integers and returns an integer as well. An
example is the function below, `differenceBetweenNumbers`, which takes two
integers and calculates the difference between the numbers. After calculating,
it returns the difference.
*/

func differenceBetweenNumbers(a: Int, b:Int) -> (Int) {
return a - b
}

func mathOperation(f:(Int, Int)->(Int), x:Int, y:Int) -> (Int){
return f(x, y)
}
let difference = mathOperation(differenceBetweenNumbers, 10, 5)

Try this:

func mathOperation(someOperationFunc: (Int, Int) -> Int, a: Int, b: Int) -> Int {
return someOperationFunc(a, b)
}

let difference = mathOperation(differenceBetweenNumbers, 26, 22)

Let me know if this works.. Its the same thing but with a different func name.

Thanks Aaron, your code works. Is it a bug of the challenge task? Or is there indeed something wrong in my code.

Hey Elgs,

I was having the same problem as you. Try removing the parathesis in between your function parameter return statement.

func mathOperation(f:(Int, Int)-> Int, x:Int, y:Int) -> (Int){
return f(x, y)
}
let difference = mathOperation(differenceBetweenNumbers, 10, 5)

Hope this helps,

Ozzie

Thanks Kirbyo. I copied and pasted your code into the challenge task, but the second task still doesn't pass. The error message is:

Bummer! Make sure you are computing the difference between two integers using the functions created and assigning the result to a constant named difference.