import Foundation

struct Person: Codable {
    let id: Int
    let name: String
    let email: String
    let active: Bool

    init(id: Int, name: String, email: String, active: Bool = true) {
        self.id = id
        self.name = name
        self.email = email
        self.active = active
    }
}

class Repository<T> {
    private var items: [Int: T] = [:]

    func add(key: Int, item: T) {
        items[key] = item
    }

    func find(key: Int) -> T? {
        return items[key]
    }

    func getAll() -> [T] {
        return Array(items.values)
    }
}

func add(_ a: Int, _ b: Int) -> Int {
    return a + b
}

enum Result<T> {
    case success(T)
    case failure(Error)
}

let repo = Repository<Person>()
repo.add(key: 1, item: Person(id: 1, name: "Alice", email: "alice@example.com"))
repo.add(key: 2, item: Person(id: 2, name: "Bob", email: "bob@example.com"))

for person in repo.getAll() {
    print("\(person.name) <\(person.email)>")
}

print("3 + 4 = \(add(3, 4))")