자바 실습문제 제가 사진 찍은 2번 문제 어떻게 푸나요?

제가 사진 찍은 2번 문제 어떻게 푸나요? public class CurrencyTest { public static void main(String[] args) { KRW won = new KRW(1500.00); USD dollar = new USD(100.50); EUR euro = new EUR(260.75); Currency[] arr = { won, dollar, euro }; for (Currency c : arr) { c.printInfo(); } } } abstract class Currency { protected double amount; // 금액 public Currency(double amount) { this.amount = amount; } public abstract void printInfo(); } class KRW extends Currency { public KRW(double amount) { super(amount); } @Override public void printInfo() { System.out.println("KRW: " + amount + " 원"); } } class USD extends Currency { public USD(double amount) { super(amount); } @Override public void printInfo() { System.out.println("USD: " + amount + " 달러"); } } class EUR extends Currency { public EUR(double amount) { super(amount); } @Override public void printInfo() { System.out.println("EUR: " + amount + " 유로"); } }

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