부모 클래스가 있을 때 이니셜라이저 위임

Square.swift

class Shape {
    var numberOfSides: Int = 0
    var name: String
    
    init(name: String) {
        self.name = name
    }
}

class Square: Shape {
    var sideLength: Double
    
    init(sideLength: Double, name: String) {
        self.sideLength = sideLength
        super.init(name: name)
    }
}

let square = Square(sideLength: 33.3, name: "운동장")