Fibs.swift

func recursiveFib(position: Int) -> Int {
    if position == 0 || position == 1 {
        return position
    }
    
    return recursiveFib(position: position - 1) + recursiveFib(position: position - 2)
}

func dynamicFib(position: Int) -> Int {
    
    switch position {
    case 0:
        return 1
    case 1:
        return 1
    default:
        var cache: [Int] = [1,1]
        for cursor in 2...position {
            let next = cache[cursor - 1] + cache[cursor - 2]
            cache.append(next)
        }
        return cache[position]
    }
}