國立暨南國際大學 114 學年度第二學期小考試卷

1. (10%) After you run the following program on a Windows PC, what will be the sizes of "a.txt" and "b.dat", respectively?
   // Size of Files
   #define _CRT_SECURE_NO_WARNINGS
   #include <iostream>
   struct Box {
       unsigned short length;
       unsigned short width;
       unsigned short height;
   };
   
   int main() {
       Box b[] = { {1, 2, 3}, {4, 5, 6}, {7, 8, 9} };
       FILE* f = fopen("a.txt", "w");
       for (size_t i=0; i<sizeof(b)/sizeof(b[0]); ++i)
           fprintf(f, "%d %d %d\n", b[i].length, b[i].width, b[i].height);
       fclose(f);
   
       f = fopen("b.dat", "wb");
       fwrite(b, sizeof(b[0]), sizeof(b)/sizeof(b[0]), f);
       fclose(f);
       return 0;
   }
   
   
2. (10%) Determine whether the syntax of the following code is correct or not.  If it is correct, predict its output.  If it is incorrect, point out the mistake(s).
   // struct tm
   #include <cstdio>
   #include <ctime>
   int main() {
       time_t t = time(0);
       struct tm* now = localtime(&t);
       printf("%d-%d-%d\n", now->tm_year, now->tm_mon, now->tm_mday);
       return 0;
   }
   
   
3. (10%) Determine whether the syntax of the following code is correct or not.  If it is correct, predict its output.  If it is incorrect, point out the mistake(s).
   // Function Pointers
   #include <iostream>
   int add(int a, int b) { return a + b; }
   int mod(int a, int b) { return a % b; }
   
   int main() {
       int *f[2](int, int)  = { add, mod };
       for (size_t i=0; i<sizeof(f)/sizeof(f[0]); ++i)
           std::cout << f[i](5, 3) << std::endl;
       return 0;
   }