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   9 <title>4.1.1 Array Initialization</title>
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  15 <H3>4.1.1 Array Initialization</H3>
  16
  17 <p>Although it is not possible
  18 to assign to all elements of an array at once
  19 using an assignment expression,
  20 it is possible to initialize some or all elements of an array
  21 when the array is defined.
  22 The syntax looks like this:
  23 <pre>
  24         int a[10] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
  25 </pre>
  26 The list of values,
  27 enclosed in braces <TT>{}</TT>,
  28 separated by commas,
  29 provides the initial values for successive elements of the array.
  30 </p><p>(Under older, pre-ANSI C compilers,
  31 you could not always supply initializers for
  32 ``local'' arrays inside functions;
  33 you could only initialize ``global'' arrays,
  34 those outside of any function.
  35 Those compilers are now rare,
  36 so you shouldn't have to worry about this distinction any more.
  37 We'll talk more about local and global variables
  38 later in this chapter.)
  39 </p><p>If there are fewer initializers than elements in the array,
  40 the remaining elements are automatically initialized to 0.
  41 For example,
  42 <pre>
  43         int a[10] = {0, 1, 2, 3, 4, 5, 6};
  44 </pre>
  45 would initialize <TT>a[7]</TT>, <TT>a[8]</TT>, and <TT>a[9]</TT> to 0.
  46 When an array definition includes an initializer,
  47 the array dimension may be omitted,
  48 and the compiler will infer the dimension
  49 from the number of initializers.
  50 For example,
  51 <pre>
  52         int b[] = {10, 11, 12, 13, 14};
  53 </pre>
  54 would declare, define, and initialize
  55 an array <TT>b</TT> of 5 elements
  56 (i.e. just as if you'd typed <TT>int b[5]</TT>).
  57 Only the dimension is omitted;
  58 the brackets <TT>[]</TT> remain
  59 to indicate that <TT>b</TT> is in fact an array.
  60 </p><p>In the case of arrays of <TT>char</TT>,
  61 the initializer may be a string constant:
  62 <pre>
  63         char s1[7] = "Hello,";
  64         char s2[10] = "there,";
  65         char s3[] = "world!";
  66 </pre>
  67
  68 As before,
  69 if
  70 the dimension is omitted,
  71 it is inferred from the size of the string initializer.
  72 (We haven't covered strings in detail yet--we'll
  73 do so in chapter 8--but
  74 it turns out that all strings in C
  75 are terminated by a
  76 special character with the value 0.
  77 Therefore, the array <TT>s3</TT> will be of size 7,
  78 and the explicitly-sized <TT>s1</TT>
  79 does need to be of size at least 7.
  80 For <TT>s2</TT>, the last 4 characters in the array
  81 will all end up being this zero-value character.)
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  91 This page by <a href="http://www.eskimo.com/~scs/">Steve Summit</a>
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