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Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and a supportive community. Start your free trial today. # My code runs correctly in xcode but it doesn't pass the review process

Here are two variations that both work:

func iMap<T, U>(_ array: Array<T>,_ transformation: (T) -> U) -> Array<U> { var transArray: [U] = [] for i in 0..<array.count { transArray.append(transformation(array[i])) } return transArray }

func square(_ first: Int) -> Int {

```return first * first
```

}

iMap([1,2,3,4,5], square)

func map<T, U>(array: Array<T>,transformation: (T) -> U) -> Array<U> { var transArray: [U] = [] for i in 0..<array.count { transArray.append(transformation(array[i])) } return transArray } map(array: [1,2,3,4,5], transformation: square)

generics.swift
```func map<T, U>(_ array: Array<T>,_ transformation: (T) -> U) -> Array<U> {
var transArray: [U] = []
for i in 1...array.count {
transArray.append(transformation(array[i]))
}
return transArray
}
``` Try this

```func map<T, U>(array: [T], transformation: (T) -> U) -> [U] {
var newArray = [U]()

for values in array {
newArray.append(transformation(values))
}
return newArray
}
```