tail-call-optimization-swift

func recursiveAdder(list:[Int]) -> Int {
    
    switch list.count {

    case 0:
        return 0
    case 1:
        return list.first!
    case 2:
        return list.first! + list.last!
    default:
        let firstTwo:[Int] = [list.first! + list[1]]
        let rest = list[2...list.count-1]
        return recursiveAdder(firstTwo + rest)
    }
}


let numbers = 1...9000

let result = recursiveAdder(numbers.map { $0 } )

println(result)