추상 클래스(abstract) using System; using System.Collections.Generic; namespace CSharp { abstract class Monster { public abstract void Shout(); } class Orc : Monster { public override void Shout() { Console.WriteLine("오크~~"); } } class Skeleton : Monster { public override void Shout() { Console.WriteLine("빠각~~"); } } class SkeletonOrc : Orc, Skeleton // ❌❌ 컴파일 에러 ! { } class Program { static void Mai..