2022_10_07 연습 04 MainClass & Calculator & Computer (상속+오버라이팅+오버로딩)

MainClass

package quiz06;

public class MainClass {
	public static void main(String[] args) {
		
		Calculator cal = new Calculator();
		
		System.out.println(cal.result);
		
		System.out.println(cal.add(10));

		System.out.println(cal.circle(4));
		
		System.out.println("===============computer===========");
		
		Computer com = new Computer();
		
		
		System.out.println("더한 값은 : " + com.add(10));
		
		com.circle(3);
		System.out.println("원의 넓이는 : " + com.circle(4));
		
		com.rect(5);
		System.out.println("정사각형의 넓이는 : " + com.rect(3));
		
		com.rect(5, 4);
		System.out.println("직사각형의 넓이는 : " + com.rect(3, 3));
		
		com.rect(5, 4, 5);
		System.out.println("직육면체의 넓이는 : " + com.rect(3, 3, 3));
		
		
		
		
	}

}

Calculator 클래스 (부모클래스 )

package quiz06;

public class Calculator {
	
	int result;
	double pi = 3.14;
	
	Calculator(){
		
	}
	
	
	int add(int a) {
		result+=a;
		return result;
	}
	
	double circle(int a) {
		
		return (pi * a * a);
	}

}​

Computer 클래스 (자식클래스 = Calculator클래스를 상속하고 circle(int a)메서드를 오버라이팅 하고 double rect()메서드를 오버로딩함 )

package quiz06;

public class Computer extends Calculator {
	
	Computer(){
		
	}
	
	double circle(int a) {
	
		return  (Math.PI*a*a);
	}
	
	double rect(double a){
		return  (a*a);
		
	}
	
	double rect(double a,double b){
		return (a*b);
	}
	
	double rect(double a,double b,double c){
		return  (a*b*c);
	}

}