國立暨南國際大學 102 學年度第二學期小考試卷

1. (10%) Determine whether the following code is correct or not.  If it is correct, predict its output.  If it is incorrect, point out the mistake(s).
   // Size of an Object
   // Assuming the program is running on a 64-bit computer
   #include <iostream>
   using std::cout;
   using std::endl;
   
   class CText
   {
   public:
       char* ptext;
   
       CText(const char* s)
       {
           ptext = new char[strlen(s)+1];
           strcpy(ptext, s);
       }
   };
   
   int main()
   {
       CText a("NCNU"), b("Berkeley");
       cout << sizeof(a) << strlen(a.ptext) << endl;
       cout << sizeof(b) << strlen(b.ptext) << endl;
       return 0;
   }
   
   
   
2. (10%) Determine whether the following code is correct or not.  If it is correct, predict its output.  If it is incorrect, point out the mistake(s).
   
   // Class Destructors (P.435)
   #include <iostream>
   using std::cout;
   using std::endl;
   
   class CText
   {
   public:
       char* ptext;
   
       CText(const char* s)
       {
           ptext = new char[strlen(s)+1];
           strcpy(ptext, s);
       }
   
       ~CText()
       {
           cout << "Destructor called to release the memory of "
                   << ptext << endl;
           delete ptext;
       }
   };
   
   int main()
   {
       CText c("Coconut"), m("Mango");
       return 0;
   }
   
   
   
3. (10%) Determine whether the following code is correct or not.  If it is correct, predict its output.  If it is incorrect, point out the mistake(s).
   
   // Implementing a Copy Constructor (P.442)
   #include <iostream>
   using std::cout;
   using std::endl;
   
   class CText
   {
   public:
       char* ptext;
   
       CText(char* s)
       {
           ptext = new char[strlen(s)+1];
           strcpy(ptext, s);
       }
   
       ~CText()
       {
           if (ptext)
               cout << "Destructor called for " << ptext << endl;
           else
               cout << "Destructor called, but no memory needs "
                    << "to be releases." << endl;
       }
   };
   
   int main()
   {
       CText b("Banana");
       CText a(b);
       *a.ptext = 'b';
       return 0;
   }
   
   
   
4. (10%) 江蕙的「落雨聲」歌詞中，哪一段表達了「樹欲靜而風不止，子欲養而親不在」的感慨?