13年题。

OOP/13Exam/3.3.cpp

@@ -0,0 +1,31 @@
+#include <iostream>
+using namespace std;
+class Base {
+    private:
+    char c;
+
+    public:
+    Base(char n): c(n) {}
+    virtual ~Base() {
+        cout << c;
+    }
+};
+
+class Der:public Base {
+    private:
+    char c;
+    public:
+    Der(char n):Base(n + 1), c(n) {}
+    ~Der(){
+        cout << c;
+    }
+};
+
+int main() {
+    Der('X');
+    return 0;
+}
+
+/*
+XY
+*/