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<h3 class="section">6.57 Binary constants using the &lsquo;<samp><span class="samp">0b</span></samp>&rsquo; prefix</h3>

<p><a name="index-Binary-constants-using-the-_0040samp_007b0b_007d-prefix-3156"></a>
Integer constants can be written as binary constants, consisting of a
sequence of &lsquo;<samp><span class="samp">0</span></samp>&rsquo; and &lsquo;<samp><span class="samp">1</span></samp>&rsquo; digits, prefixed by &lsquo;<samp><span class="samp">0b</span></samp>&rsquo; or
&lsquo;<samp><span class="samp">0B</span></samp>&rsquo;.  This is particularly useful in environments that operate a
lot on the bit-level (like microcontrollers).

 <p>The following statements are identical:

<pre class="smallexample">     i =       42;
     i =     0x2a;
     i =      052;
     i = 0b101010;
</pre>
 <p>The type of these constants follows the same rules as for octal or
hexadecimal integer constants, so suffixes like &lsquo;<samp><span class="samp">L</span></samp>&rsquo; or &lsquo;<samp><span class="samp">UL</span></samp>&rsquo;
can be applied.

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