If the divisor is a <a href="#Constants">constant</a>, it must not be zero.
If the divisor is zero at run time, a <a href="#Run_time_panics">run-time panic</a> occurs.
If the dividend is non-negative and the divisor is a constant power of 2,
the division may be replaced by a right shift, and computing the remainder may
be replaced by a bitwise AND operation:
</p>

<pre>
 x     x / 4     x % 4     x &gt;&gt; 2     x &amp; 3