國立暨南國際大學 104 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).
   // Operator Overloading (P.331)
   #include <iostream>
   
   class CRational
   {
       int numerator;
       int denominator;
   public:
       CRational(int n, int d): numerator(n), denominator(d) {}
   
       bool operator<(CRational b)
       {
           if (numerator * b.denominator < denominator * b.numerator)
               return true;
           else
               return false;
       }
   };
   
   int main()
   {
       CRational a(2,3), b(1,2);
       std::cout << (a<b?"a<b":"a>=b") << std::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).
   
   // The Size of a Vector (P.495)
   #include <iostream>
   #include <vector>
   using std::vector;
   
   int main()
   {
       vector<int> p, q;
       for (int i=0; i<10+1; i++) p.push_back(0);
       for (int i=0; i<15+1; i++) q.push_back(0);
       for (int i=0; i<20+1; i++) p.push_back(0);
       std::cout << p.size() << '\t' << q.size() << std::endl;
       return 0;
   }