第5次作业--对象的创建与使用

package Sum;
import java.util.*;
class Rect {
    double length;
    double width;
    double perimeter;
    double area;           //长宽面积周长成员变量
     Rect(double n, double k) {
        length = n;
        width = k;
    }                        //构造方法 将值赋给成员变量
    double area1() {
        area = length * width;
        return area;
    }                        //计算返回面积
    double perimeter1() {
        perimeter = 2 * (length + width);
        return perimeter;
    }                        //计算返回周长
}
public class Rectangle {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println("请输入矩形的长和宽：");
        Scanner reader = new Scanner(System.in);
        double num1 = reader.nextDouble();
        double num2 = reader.nextDouble();    
        Rect a = new Rect(num1, num2);            //创建对象
        System.out.println("矩形的面积为：" + a.area1());
        System.out.println("矩形的周长为：" + a.perimeter1());
    }
}