國立暨南國際大學 101 學年度第一學期小考試卷

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).
   
   // Two's Complement
   #include <iostream>
   
   int main()
   {
       signed short m = 1<<15;
       std::cout << m << 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).
   
   // Increment operator
   #include <iostream>
   
   int main()
   {
       int i;
       int sum = 0;
       for (i=1; i<6; i++)
           sum += i++;
           std::cout << sum << std::endl;
       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).
   
   // Bitwise-operation
   #include <iostream>
   
   int main()
   {
       signed short n = ~0;
       std::cout << n << std::endl;
       return 0;
   }
   
   
   
4. (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).
   
   // Counting letters in a string
   #include <iostream>
   
   int main()
   {
       char str[] = "The Teeth of the Tiger";
       char c;
       int i, count(0);
       for (i=0; i < sizeof(str); i++)
       {
           c = str[i];
           if ('a' <= c && c <= 'z')
               count++;
       }
       std::cout << count << std::endl;
       return 0;
   }
   
   
5. (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).
   
   // Nested-loop
   #include <iostream>
   using std::cout;
   using std::endl;
   
   void Print(int n)
   {
       int i,j;
       for (i=0; i<n; i++) cout << '*'; cout << endl;
       for (i=1; i<n-1; i++)
       {
           cout << '*';
           for (j=1; j<n-1; j++) cout << ' ';
           cout << '*' << endl;
       }
       for (i=0; i<n; i++) cout << '*'; cout << endl;
   }
   
   int main()
   {   Print(3);
       return 0;
   }
   
   
6. (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).
   
   // Two-dimensional array
   #include <iostream>
   using std::cout;
   using std::endl;
   
   int main()
   {
       int i, j;
       int A[3][3] = { { 1, 2, 3}, {4, 5, 6}, {7, 8, 9} };
       int B[9] = { 0 };
       for (i=0; i<3; i++)
           for (j=0; j<3; j++)
               B[j * 3 + i] = A[i][j];
       for (i=0; i<9; i++)
           cout << B[i];
       cout << endl;
       return 0;
   }
   
   
7. (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).
   
   // Default values of function parameters (P.302)
   #include <iostream>
   
   int pdo_it(int a, int b, int c = 30)
   { return a + b + c; }
   
   int pdo_it(int a, int b)
   { return a * b; }
   
   int main()
   {
       std::cout << pdo_it(12, 18) << std::endl;
       std::cout << pdo_it(2012, 12, 18) << std::endl;
       std::cout << pdo_it( pdo_it(20,12), 12, 18 )
               << std::endl;
       return 0;
   }
   
   
   
8. (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).
   
   // Pointers to Functions
   #include <iostream>
   
   int sum(int a, int b)
   { return a + b; }
   
   int product(int a, int b)
   { return a * b; }
   
   int main()
   {
       int (*pfun)[2](int, int) = { sum, product };
       std::cout << pfun[1](2, 3) << std::endl;
       return 0;
   }
   
   
   
9. (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).
   
   // Traverse a linked-list
   #include <iostream>
   
   struct ListElement
   {
       int value;
       ListElement* pNext;
   };
   
   void Print(ListElement p)
   {
       std::cout << p.value;
       if (p.pNext != NULL)
           Print(*p.pNext);    
           // Note the precedence of these two operators
   }
   
   int main()
   {
       ListElement LE1 = { 1, NULL };
       ListElement LE2 = { 3, &LE1 };
       ListElement LE3 = { 2, &LE2 };
       ListElement LE4 = { 4, &LE3 };
   
       Print(LE4);
       std::cout << std::endl;
       return 0;
   }
   
   
   
10. (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).
    
    // Representing a polynomial with a linked-list
    #include <iostream>
    
    struct ListElement
    {
        int value;
        ListElement* pNext;
    };
    
    void Print(ListElement* p)
    {
        int i;
        for (i = 0; p != NULL; p = p->pNext, i++)
        {
            std::cout << "+" << p->value;
            if (i > 0)
            {
                std::cout << "X";
                if (i > 1)
                    std::cout << "^" << i;
            }
    
        }
        std::cout << std::endl;
    }
    
    int main()
    {
        ListElement LE4 = { 1, NULL };
        ListElement LE3 = { 4, &LE4 };
        ListElement LE2 = { 3, &LE3 };
        ListElement LE1 = { 2, &LE2 };
    
        Print(&LE1);
        return 0;
    }