diff --git a/w4/类图/屏幕截图 2026-03-28 124033.png b/w4/类图/屏幕截图 2026-03-28 124033.png
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diff --git a/w4/类图/类图代码 b/w4/类图/类图代码
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+classDiagram
+    class Shape {
+        <<abstract>>
+        +getArea() double*
+    }
+    class Circle {
+        -radius : double
+        +Circle(double)
+        +getArea() double
+    }
+    class Rectangle {
+        -length : double
+        -width : double
+        +Rectangle(double, double)
+        +getArea() double
+    }
+    class Triangle {
+        -base : double
+        -height : double
+        +Triangle(double, double)
+        +getArea() double
+    }
+    class ShapeUtil {
+        +printArea(Shape) void
+    }
+    Shape <|-- Circle
+    Shape <|-- Rectangle
+    Shape <|-- Triangle
+    ShapeUtil --> Shape : uses
\ No newline at end of file