上传文件至 'w4'

w4/Triangle.java

@@ -0,0 +1,17 @@
+public class Triangle extends Shape {
+    private double base;
+    private double height;
+
+    public Triangle(double base, double height) {
+        this.base = base;
+        this.height = height;
+    }
+
+    public double getBase()       { return base; }
+    public double getTriHeight()  { return height; }
+
+    @Override
+    public double getArea() {
+        return 0.5 * base * height;
+    }
+}