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<H1><A NAME="SECTION007700000000000000000"></A>
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5.7 Shifting operations
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<P>
The shifting operations have lower priority than the arithmetic
operations:

<P>
<dl><dd><pre class=verbatim>
shift_expr:     a_expr | shift_expr ( "&lt;&lt;" | "&gt;&gt;" ) a_expr
</pre></dl>

<P>
These operators accept plain or long integers as arguments.  The
arguments are converted to a common type.  They shift the first
argument to the left or right by the number of bits given by the
second argument.

<P>
A right shift by <var>n</var> bits is defined as division by
<tt>pow(2,<var>n</var>)</tt>.  A left shift by <var>n</var> bits is defined as
multiplication with <tt>pow(2,<var>n</var>)</tt>; for plain integers there is
no overflow check so in that case the operation drops bits and flips
the sign if the result is not less than <tt>pow(2,31)</tt> in absolute
value.  Negative shift counts raise a <tt class=exception>ValueError</tt>
exception.
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