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<a name="wi-arithmetic-on-poly_005fints"></a>
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<p>
Next: <a href="Division-of-poly_005fints.html#Division-of-poly_005fints" accesskey="n" rel="next">Division of <code>poly_int</code>s</a>, Previous: <a href="Using-poly_005fint-with-C_002b_002b-arithmetic-operators.html#Using-poly_005fint-with-C_002b_002b-arithmetic-operators" accesskey="p" rel="prev">Using <code>poly_int</code> with C++ arithmetic operators</a>, Up: <a href="Arithmetic-on-poly_005fints.html#Arithmetic-on-poly_005fints" accesskey="u" rel="up">Arithmetic on <code>poly_int</code>s</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<a name="wi-arithmetic-on-poly_005fints-1"></a>
<h4 class="subsection">10.4.2 <code>wi</code> arithmetic on <code>poly_int</code>s</h4>

<p>As well as the C++ operators, <code>poly_int</code> supports the following
<code>wi</code> routines:
</p>
<div class="smallexample">
<pre class="smallexample">wi::neg (<var>p1</var>, &amp;<var>overflow</var>)

wi::add (<var>p1</var>, <var>p2</var>)
wi::add (<var>p1</var>, <var>c2</var>)
wi::add (<var>c1</var>, <var>p1</var>)
wi::add (<var>p1</var>, <var>p2</var>, <var>sign</var>, &amp;<var>overflow</var>)

wi::sub (<var>p1</var>, <var>p2</var>)
wi::sub (<var>p1</var>, <var>c2</var>)
wi::sub (<var>c1</var>, <var>p1</var>)
wi::sub (<var>p1</var>, <var>p2</var>, <var>sign</var>, &amp;<var>overflow</var>)

wi::mul (<var>p1</var>, <var>c2</var>)
wi::mul (<var>c1</var>, <var>p1</var>)
wi::mul (<var>p1</var>, <var>c2</var>, <var>sign</var>, &amp;<var>overflow</var>)

wi::lshift (<var>p1</var>, <var>c2</var>)
</pre></div>

<p>These routines just check whether overflow occurs on any individual
coefficient; it is not possible to know at compile time whether the
final runtime value would overflow.
</p>


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