Fibonacci sequence in Swift

Fibber.swift

func fibber(n:Int) -> Int { 
    switch n { 
    case 0: 
        return 0 
    case 1: 
        return 1 
    default: 
        return fibber(n-1) + fibber(n-2) 
     } 
}  

I would have rather done it without recursion (recursion is evil), such as:

func fibo(_ n:Int) -> Int {

    var a = 0
    var b = 1

    for _ in 0..<n {
        a += b
        b = a - b
    }

    return a
}

it is way faster to execute!