13年题。

OOP/13Exam/2.1.cpp

@@ -0,0 +1,33 @@
+// 在下面基类Base和派生类Derived中增加成员函数show，使得程序运行结果如下：
+// Base
+// Derived
+
+#include <iostream>
+using namespace std;
+class Base {
+public:
+    // _________________________;
+
+    virtual void show() {
+        cout << "Base" << endl;
+    }
+};
+
+class Derived : public Base {
+public:
+    // __________________________;
+
+    virtual void show() {
+        cout << "Derived" << endl;
+    }
+};
+
+int main() {
+    Base b, *ptr;
+    Derived d;
+    ptr = &b;
+    ptr->show();
+    ptr = &d;
+    ptr->show();
+    return 0;
+};