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  58. <h3 class="subsection">2.2.2 Blocking</h3>
  59. <p>After the bit string is obtained as described above, it is grouped into
  60. blocks of six. Continuing with the example, the string
  61. </p>
  62. <table><tr><td>&nbsp;</td><td><pre class="example">111111101011110010001001100010100010100100100
  63. </pre></td></tr></table>
  64. <p>would be grouped as
  65. </p>
  66. <table><tr><td>&nbsp;</td><td><pre class="example">111111 101011 110010 001001 100010 100010 100100 100
  67. </pre></td></tr></table>
  68. <p>Because the number of bits isn&rsquo;t a multiple of six, the last group has to
  69. be padded with zeros, to give
  70. </p>
  71. <table><tr><td>&nbsp;</td><td><pre class="example">111111 101011 110010 001001 100010 100010 100100 100000
  72. </pre></td></tr></table>
  73. <p>Each of these six bit substrings is then treated as a binary number,
  74. with the most significant bit on the left. The numbers expressed in
  75. decimal are
  76. </p>
  77. <table><tr><td>&nbsp;</td><td><pre class="example">63 43 50 9 34 34 36 32
  78. </pre></td></tr></table>
  79. <a name="index-character-codes"></a>
  80. <p>The character codes for the characters to be written are obtained by
  81. adding sixty to each of these numbers, so as to ensure that they will be
  82. printable characters. The resulting character codes are
  83. </p>
  84. <table><tr><td>&nbsp;</td><td><pre class="example">123 103 110 69 94 94 96 92
  85. </pre></td></tr></table>
  86. <p>which implies that the tree in the example could be written to a file as
  87. <code>{gnE^^`\</code>.
  88. </p>
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