class DeepNeuralNetwork {

    let iterations: Int
    let learningRate: Double

    private var layers = [Layer]()

    init(iterations: Int, learningRate: Double) {
        self.iterations = iterations
        self.learningRate = learningRate
    }

    func add(layer: Layer) {
        layers.append(layer)
    }

    func compile() {
        for i in 0..<layers.count {
            layers[i].initialize(
                previous: i == 0 ? nil : layers[i - 1],
                next: i == layers.count - 1 ? nil : layers[i + 1]
            )
        }
    }
}