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  67. <a name="Binary-Constants-using-the-0b-Prefix"></a>
  68. <h3 class="section">6.65 Binary Constants using the &lsquo;<samp>0b</samp>&rsquo; Prefix</h3>
  69. <a name="index-Binary-constants-using-the-0b-prefix"></a>
  70. <p>Integer constants can be written as binary constants, consisting of a
  71. sequence of &lsquo;<samp>0</samp>&rsquo; and &lsquo;<samp>1</samp>&rsquo; digits, prefixed by &lsquo;<samp>0b</samp>&rsquo; or
  72. &lsquo;<samp>0B</samp>&rsquo;. This is particularly useful in environments that operate a
  73. lot on the bit level (like microcontrollers).
  74. </p>
  75. <p>The following statements are identical:
  76. </p>
  77. <div class="smallexample">
  78. <pre class="smallexample">i = 42;
  79. i = 0x2a;
  80. i = 052;
  81. i = 0b101010;
  82. </pre></div>
  83. <p>The type of these constants follows the same rules as for octal or
  84. hexadecimal integer constants, so suffixes like &lsquo;<samp>L</samp>&rsquo; or &lsquo;<samp>UL</samp>&rsquo;
  85. can be applied.
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