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Arrays

• Declaring an array is very similar to declaring a vector.

  double salaries[10]; /* array */
  
  
  
  /* compare to.... */
  vector<double> salaries(10); 
  

• Arrays can never change size.
• The array size must be set when the program is compiled. (You can't ask the user how many elements and then allocate a sufficient number).
• When defining an array, you must guess on the maximum number of elements you need to store.

  const int SALARIES_CAPACITY = 100;
  double salaries[SALARIES_CAPACITY];
  

• You must keep a constant to hold the capacity of the array.
• You must keep a companion variable that counts how many elements are actually used.

  int salaries_size = 0;
  while (more && salaries_size < SALARIES_CAPACITY)
  {
     cout << "Enter salary or 0 to quit: ";
     double x;
     cin >> x;
     if (cin.fail() || x == 0)
        more = false;
  
     else
     {
        salaries[salaries_size] = x;
        salaries_size++;
     }
  }
  

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