[빈칸] Talkable {
var topic: String { get set }
var language: String { get }
func talk()
init(topic: String, language: String)
}
struct Person: Talkable {
var topic: String
let language: String
func talk() {
print("\(topic)에 대해 \(language)로 말합니다")
}
init(topic: String, language: String) {
self.topic = topic
self.language = language
}
}
정답 :
protocol
[빈칸] Int {
var isEven: Bool {
return self % 2 == 0
}
}
print(1.isEven) // false
[빈칸] Int {
func multiply(by n: Int) -> Int {
return self * n
}
}
print(3.multiply(by: 2)) // 6
정답 :
extension