國立暨南國際大學 109 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).
   /* Pass-by-Reference */
   #include <iostream>
   using std::cout;
   using std::endl;
   
   void swap(int a, int& b) {
       int temp = a;
       a = b;
       b = temp;
   }
   
   int main() {
       int x = 3, y = 18;
       swap(x, y);
       cout << x << y << 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).
   /* Function Pointer */
   #include <iostream>
   using std::cout;
   using std::endl;
   
   int square(int n) { return n * n; }
   int cube(int n) { return n * n * n; }
   
   int main()
   {
       int *f(int) = square;
       cout << f(-5) << endl;
       f = cube;
       cout << f(-5) << endl;
       return 0;
   }
   
   
   
3. (10%) Suppose you run the following code on an Intel x86 processor, where an unsigned integer is stored in 2-byte little-endian. Predict its output.
   /* void* and Little Endian */
   #include <iostream>
   using std::cout;
   using std::endl;
   
   int main()
   {
       short n = 0x4142;
       void* p = &n;
       char* p1 = static_cast<char*>(p);
       short* p2 = static_cast<short*>(p);
       cout << *p1 << *p2 << endl;
       // Can we "cout << *p" ?
   
       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).
   /* Pointer Arithmetic */
   #include <iostream>
   using std::cout;
   using std::endl;
   
   int main()
   {
       unsigned short a[] = {1, 3, 5, 7, 9};
       cout << sizeof(a[0]);
       cout << a[1] << *(a+2) << endl;
   
       return 0;
   }