8.1 a) arrays. b) variables, type. c) foreach. d) index (or position number). e) two-dimensional. f) foreach (double d in numbers). g) an array of strings, usually called args. h) args.Length. i) test. j) params modifier. k) getter-only.

8.2 The answers to Self-Review Exercise 8.2 are:

1. False. An array can store only values of the same type.

2. False. An array index must be an integer or an integer expression.

3. For individual value-type elements of an array: False. A called method receives and manipulates a copy of the value of such an element, so modifications do not affect the original value. If the reference of an array is passed to a method, however, modifications to the array elements made in the called method are indeed reflected in the original. For individual elements of a reference type: True. A called method receives a copy of the reference of such an element, and changes to the referenced object will be reflected in the original array element.

4. False. Command-line arguments are separated by whitespace.

5. False. As of C# 6, you can use auto-property initialization in auto-implemented property declarations.

8.3 The answers to Self-Review Exercise 8.3 are:

1. const int ArraySize = 10;

2. var fractions = new double[ArraySize];

3. fractions[3]

4. fractions[9] = 1.667;

5. fractions[6] = 3.333;

6.  

   
   var total = 0.0;
   for (var x = 0; x < fractions.Length; ++x)
   {
      total += fractions[x];
   }
   

7.  

   
   var total = 0.0;
   foreach (var element in fractions)
   {
      total += element;
   }
   

8.4 The answers to Self-Review Exercise 8.4 are:

1. var table = new int[ArraySize, ArraySize];

2. Nine.

3.  

   
   for (var x = 0; x < table.GetLength(0); ++x)
   {
      for (var y = 0; y < table.GetLength(1); ++y)
      {
         table[x, y] = x + y;
      }
   }
   

8.5 The answers to Self-Review Exercise 8.5 are:

1. Error: Assigning a value to a constant after it’s been initialized.

   Correction: Assign the correct value to the constant in the const declaration.

2. Error: Referencing an array element outside the bounds of the array (b[10]).

   Correction: Change the <= operator to <.

3. Error: Array indexing is performed incorrectly.

   Correction: Change the statement to a[1, 1] = 5;.