Rational Number (1)

1. Suppose you have defined a struct:

   struct Rational {
       int numerator;      // 分子
       int denominator;    // 分母
   };

2. Create a program which can read 5 rational numbers, and then print them out.
3. The program may run as follows:

   1/5
   2/4
   3/3
   4/2
   5/1
   1/5 2/4 3/3 4/2 5/1

4. The main function may look like:

   int main()
   {
       Rational A[N];
   
       read_rationals(A, N);
       print_rationals(A, N);
   
       return 0;
   }