HackerRank Read Input with Swift

hackerRank.swift

//Read String array separated by new line character
func readInput () -> [String]{
    let n: Int = Int(readLine()!)!
    var strs = [String]()
    (0...n-1).map { _ in
        strs.append(readLine()!.lowercased())
    }
    return strs
}

//Read Int array
func readInput () -> [Int]{

    let number: Int = Int(readLine()!)!
    let input = readLine()!
    let numbers = input.toIntArray()
    return numbers
}

extension String {
    
    func toIntArray () -> [Int]{
        let numberCharacters = self.characters.split(separator: " ")
        let numbers = numberCharacters.map { Int(String($0))! }
        return numbers
    }
}

//Source
//http://keitaito.com/blog/2017/01/27/how-to-read-standard-input-in-swift.html