diff --git a/w4作业/W4-AI协助记录.txt b/w4作业/W4-AI协助记录.txt
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+AI协助记录
+1.协助提供统一处理图形的方法：class ShapeUtil
+2.修改部分语法错误
+3.针对于UML类图实线和虚线疑问的区别进行解释
+
+组合VS继承
+1.继承是is关系，组合是has关系
+2.继承是父类和子类的关系，它们具有共同特征；而组合是所属关系。例如：电脑是一种电器，是继承关系，用extend；电脑拥有显示屏，是组合关系，用Screen screen。
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diff --git a/w4作业/W4图形面积计算器重构.ini b/w4作业/W4图形面积计算器重构.ini
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+W4  图形面积计算器重构
+public abstract class Shape {
+    public abstract double getArea();
+}
+// 圆形类，继承自 Shape
+class Circle extends Shape {
+    private double radius;
+    public Circle(double radius) {
+        this.radius = radius;
+    }    
+    @Override
+    public double getArea() {
+        return Math.PI * radius * radius;
+    }
+}
+// 矩形类，继承自 Shape
+class Rectangle extends Shape {
+    private double width;
+    private double height;
+    public Rectangle(double width, double height) {
+        this.width = width;
+        this.height = height;
+    }
+    @Override
+    public double getArea() {
+        return width * height;
+    }
+}
+// 三角形类，继承自 Shape
+class Triangle extends Shape {
+    private double base;
+    private double height;
+    public Triangle(double base, double height) {
+        this.base = base;
+        this.height = height;
+    }    
+    @Override
+    public double getArea() {
+        return 0.5 * base * height;
+    }
+}
+// 图形工具类，提供统一处理图形的方法
+class ShapeUtil {
+    // 打印图形面积的方法，接受任意 Shape 子类对象
+    public static void printArea(Shape shape) {
+        System.out.println("图形面积: " + shape.getArea());
+    }
+    public static void main(String[] args) {
+        // 创建各种图形对象
+        Shape circle = new Circle(5.0);
+        Shape rectangle = new Rectangle(4.0, 6.0);
+        Shape triangle = new Triangle(3.0, 4.0);
+        // 统一打印各图形面积
+        System.out.println("圆形:");
+        printArea(circle);    
+        System.out.println("矩形:");
+        printArea(rectangle);      
+        System.out.println("三角形:");
+        printArea(triangle);
+    }
+}
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