HackerRank Swift stdin stdout

hackerrank.swift

import Foundation

//MARK: STDIN STDOUT
func readData() -> NSData {
    return NSFileHandle.fileHandleWithStandardInput().availableData
}

func readString() -> String {
    return String(data: readData(), encoding:NSUTF8StringEncoding)!.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
}

func readInt() -> Int {
    return Int(readString())!
}

func readArrayOfStrings() -> Array<String> {
    return readString().componentsSeparatedByCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
}

func readArrayOfInts() -> Array<Int> {
    return readArrayOfStrings().map {
        (str: String) -> Int in
        return Int(str)!
    }
}

func readArrayOfDoubles() -> Array<Double> {
    return readArrayOfStrings().map {
        (str: String) -> Double in
        return Double(str)!
    }
}