1<html> 2<head> 3<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> 4<title>Permutation Iterator</title> 5<link rel="stylesheet" href="../../../../../../doc/src/boostbook.css" type="text/css"> 6<meta name="generator" content="DocBook XSL Stylesheets V1.79.1"> 7<link rel="home" href="../../index.html" title="Chapter 1. Boost.Iterator"> 8<link rel="up" href="../specialized.html" title="Specialized Adaptors"> 9<link rel="prev" href="indirect.html" title="Indirect Iterator"> 10<link rel="next" href="reverse.html" title="Reverse Iterator"> 11</head> 12<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"> 13<table cellpadding="2" width="100%"><tr> 14<td valign="top"><img alt="Boost C++ Libraries" width="277" height="86" src="../../../../../../boost.png"></td> 15<td align="center"><a href="../../../../../../index.html">Home</a></td> 16<td align="center"><a href="../../../../../../libs/libraries.htm">Libraries</a></td> 17<td align="center"><a href="http://www.boost.org/users/people.html">People</a></td> 18<td align="center"><a href="http://www.boost.org/users/faq.html">FAQ</a></td> 19<td align="center"><a href="../../../../../../more/index.htm">More</a></td> 20</tr></table> 21<hr> 22<div class="spirit-nav"> 23<a accesskey="p" href="indirect.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../specialized.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="reverse.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 24</div> 25<div class="section"> 26<div class="titlepage"><div><div><h3 class="title"> 27<a name="iterator.specialized.permutation"></a><a class="link" href="permutation.html" title="Permutation Iterator">Permutation Iterator</a> 28</h3></div></div></div> 29<p> 30 The permutation iterator adaptor provides a permuted view of a given range. 31 That is, the view includes every element of the given range but in a potentially 32 different order. The adaptor takes two arguments: 33 </p> 34<div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "> 35<li class="listitem"> 36 an iterator to the range V on which the permutation will be applied 37 </li> 38<li class="listitem"> 39 the reindexing scheme that defines how the elements of V will be permuted. 40 </li> 41</ul></div> 42<p> 43 Note that the permutation iterator is not limited to strict permutations 44 of the given range V. The distance between begin and end of the reindexing 45 iterators is allowed to be smaller compared to the size of the range V, in 46 which case the permutation iterator only provides a permutation of a subrange 47 of V. The indexes neither need to be unique. In this same context, it must 48 be noted that the past the end permutation iterator is completely defined 49 by means of the past-the-end iterator to the indices. 50 </p> 51<h3> 52<a name="iterator.specialized.permutation.h0"></a> 53 <span class="phrase"><a name="iterator.specialized.permutation.example"></a></span><a class="link" href="permutation.html#iterator.specialized.permutation.example">Example</a> 54 </h3> 55<pre class="programlisting"><span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">;</span> 56<span class="keyword">int</span> <span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> 57 58<span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">vector</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">></span> <span class="identifier">element_range_type</span><span class="special">;</span> 59<span class="keyword">typedef</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">list</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">></span> <span class="identifier">index_type</span><span class="special">;</span> 60 61<span class="keyword">static</span> <span class="keyword">const</span> <span class="keyword">int</span> <span class="identifier">element_range_size</span> <span class="special">=</span> <span class="number">10</span><span class="special">;</span> 62<span class="keyword">static</span> <span class="keyword">const</span> <span class="keyword">int</span> <span class="identifier">index_size</span> <span class="special">=</span> <span class="number">4</span><span class="special">;</span> 63 64<span class="identifier">element_range_type</span> <span class="identifier">elements</span><span class="special">(</span> <span class="identifier">element_range_size</span> <span class="special">);</span> 65<span class="keyword">for</span><span class="special">(</span><span class="identifier">element_range_type</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">el_it</span> <span class="special">=</span> <span class="identifier">elements</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()</span> <span class="special">;</span> <span class="identifier">el_it</span> <span class="special">!=</span> <span class="identifier">elements</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">el_it</span><span class="special">)</span> 66 <span class="special">*</span><span class="identifier">el_it</span> <span class="special">=</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">distance</span><span class="special">(</span><span class="identifier">elements</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">el_it</span><span class="special">);</span> 67 68<span class="identifier">index_type</span> <span class="identifier">indices</span><span class="special">(</span> <span class="identifier">index_size</span> <span class="special">);</span> 69<span class="keyword">for</span><span class="special">(</span><span class="identifier">index_type</span><span class="special">::</span><span class="identifier">iterator</span> <span class="identifier">i_it</span> <span class="special">=</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()</span> <span class="special">;</span> <span class="identifier">i_it</span> <span class="special">!=</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">i_it</span> <span class="special">)</span> 70 <span class="special">*</span><span class="identifier">i_it</span> <span class="special">=</span> <span class="identifier">element_range_size</span> <span class="special">-</span> <span class="identifier">index_size</span> <span class="special">+</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">distance</span><span class="special">(</span><span class="identifier">indices</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">i_it</span><span class="special">);</span> 71<span class="identifier">std</span><span class="special">::</span><span class="identifier">reverse</span><span class="special">(</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> <span class="special">);</span> 72 73<span class="keyword">typedef</span> <span class="identifier">permutation_iterator</span><span class="special"><</span> <span class="identifier">element_range_type</span><span class="special">::</span><span class="identifier">iterator</span><span class="special">,</span> <span class="identifier">index_type</span><span class="special">::</span><span class="identifier">iterator</span> <span class="special">></span> <span class="identifier">permutation_type</span><span class="special">;</span> 74<span class="identifier">permutation_type</span> <span class="identifier">begin</span> <span class="special">=</span> <span class="identifier">make_permutation_iterator</span><span class="special">(</span> <span class="identifier">elements</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">begin</span><span class="special">()</span> <span class="special">);</span> 75<span class="identifier">permutation_type</span> <span class="identifier">it</span> <span class="special">=</span> <span class="identifier">begin</span><span class="special">;</span> 76<span class="identifier">permutation_type</span> <span class="identifier">end</span> <span class="special">=</span> <span class="identifier">make_permutation_iterator</span><span class="special">(</span> <span class="identifier">elements</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">end</span><span class="special">()</span> <span class="special">);</span> 77 78<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"The original range is : "</span><span class="special">;</span> 79<span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span> <span class="identifier">elements</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">elements</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">ostream_iterator</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">>(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span><span class="special">,</span> <span class="string">" "</span> <span class="special">)</span> <span class="special">);</span> 80<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n"</span><span class="special">;</span> 81 82<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"The reindexing scheme is : "</span><span class="special">;</span> 83<span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">indices</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">ostream_iterator</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">>(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span><span class="special">,</span> <span class="string">" "</span> <span class="special">)</span> <span class="special">);</span> 84<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n"</span><span class="special">;</span> 85 86<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"The permutated range is : "</span><span class="special">;</span> 87<span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span> <span class="identifier">begin</span><span class="special">,</span> <span class="identifier">end</span><span class="special">,</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">ostream_iterator</span><span class="special"><</span> <span class="keyword">int</span> <span class="special">>(</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span><span class="special">,</span> <span class="string">" "</span> <span class="special">)</span> <span class="special">);</span> 88<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n"</span><span class="special">;</span> 89 90<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Elements at even indices in the permutation : "</span><span class="special">;</span> 91<span class="identifier">it</span> <span class="special">=</span> <span class="identifier">begin</span><span class="special">;</span> 92<span class="keyword">for</span><span class="special">(</span><span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span><span class="special">;</span> <span class="identifier">i</span> <span class="special"><</span> <span class="identifier">index_size</span> <span class="special">/</span> <span class="number">2</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">,</span> <span class="identifier">it</span><span class="special">+=</span><span class="number">2</span> <span class="special">)</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="special">*</span><span class="identifier">it</span> <span class="special"><<</span> <span class="string">" "</span><span class="special">;</span> 93<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n"</span><span class="special">;</span> 94 95<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Permutation backwards : "</span><span class="special">;</span> 96<span class="identifier">it</span> <span class="special">=</span> <span class="identifier">begin</span> <span class="special">+</span> <span class="special">(</span><span class="identifier">index_size</span><span class="special">);</span> 97<span class="identifier">assert</span><span class="special">(</span> <span class="identifier">it</span> <span class="special">!=</span> <span class="identifier">begin</span> <span class="special">);</span> 98<span class="keyword">for</span><span class="special">(</span> <span class="special">;</span> <span class="identifier">it</span><span class="special">--</span> <span class="special">!=</span> <span class="identifier">begin</span> <span class="special">;</span> <span class="special">)</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="special">*</span><span class="identifier">it</span> <span class="special"><<</span> <span class="string">" "</span><span class="special">;</span> 99<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n"</span><span class="special">;</span> 100 101<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"Iterate backward with stride 2 : "</span><span class="special">;</span> 102<span class="identifier">it</span> <span class="special">=</span> <span class="identifier">begin</span> <span class="special">+</span> <span class="special">(</span><span class="identifier">index_size</span> <span class="special">-</span> <span class="number">1</span><span class="special">);</span> 103<span class="keyword">for</span><span class="special">(</span><span class="identifier">i</span> <span class="special">=</span> <span class="number">0</span> <span class="special">;</span> <span class="identifier">i</span> <span class="special"><</span> <span class="identifier">index_size</span> <span class="special">/</span> <span class="number">2</span> <span class="special">;</span> <span class="special">++</span><span class="identifier">i</span><span class="special">,</span> <span class="identifier">it</span><span class="special">-=</span><span class="number">2</span> <span class="special">)</span> <span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="special">*</span><span class="identifier">it</span> <span class="special"><<</span> <span class="string">" "</span><span class="special">;</span> 104<span class="identifier">std</span><span class="special">::</span><span class="identifier">cout</span> <span class="special"><<</span> <span class="string">"\n"</span><span class="special">;</span> 105</pre> 106<p> 107 The output is: 108 </p> 109<pre class="programlisting">The original range is : 0 1 2 3 4 5 6 7 8 9 110The reindexing scheme is : 9 8 7 6 111The permutated range is : 9 8 7 6 112Elements at even indices in the permutation : 9 7 113Permutation backwards : 6 7 8 9 114Iterate backward with stride 2 : 6 8 115</pre> 116<p> 117 The source code for this example can be found <a href="../../../../example/permutation_iter_example.cpp" target="_top">here</a>. 118 </p> 119<h3> 120<a name="iterator.specialized.permutation.h1"></a> 121 <span class="phrase"><a name="iterator.specialized.permutation.reference"></a></span><a class="link" href="permutation.html#iterator.specialized.permutation.reference">Reference</a> 122 </h3> 123<h4> 124<a name="iterator.specialized.permutation.h2"></a> 125 <span class="phrase"><a name="iterator.specialized.permutation.synopsis"></a></span><a class="link" href="permutation.html#iterator.specialized.permutation.synopsis">Synopsis</a> 126 </h4> 127<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">ElementIterator</span> 128 <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">IndexIterator</span> 129 <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ValueT</span> <span class="special">=</span> <span class="identifier">use_default</span> 130 <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">CategoryT</span> <span class="special">=</span> <span class="identifier">use_default</span> 131 <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">ReferenceT</span> <span class="special">=</span> <span class="identifier">use_default</span> 132 <span class="special">,</span> <span class="keyword">class</span> <span class="identifier">DifferenceT</span> <span class="special">=</span> <span class="identifier">use_default</span> <span class="special">></span> 133<span class="keyword">class</span> <span class="identifier">permutation_iterator</span> 134<span class="special">{</span> 135<span class="keyword">public</span><span class="special">:</span> 136 <span class="identifier">permutation_iterator</span><span class="special">();</span> 137 <span class="keyword">explicit</span> <span class="identifier">permutation_iterator</span><span class="special">(</span><span class="identifier">ElementIterator</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">IndexIterator</span> <span class="identifier">y</span><span class="special">);</span> 138 139 <span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">OEIter</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">OIIter</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">V</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">C</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">R</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">D</span> <span class="special">></span> 140 <span class="identifier">permutation_iterator</span><span class="special">(</span> 141 <span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">OEIter</span><span class="special">,</span> <span class="identifier">OIIter</span><span class="special">,</span> <span class="identifier">V</span><span class="special">,</span> <span class="identifier">C</span><span class="special">,</span> <span class="identifier">R</span><span class="special">,</span> <span class="identifier">D</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">r</span> 142 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">enable_if_convertible</span><span class="special"><</span><span class="identifier">OEIter</span><span class="special">,</span> <span class="identifier">ElementIterator</span><span class="special">>::</span><span class="identifier">type</span><span class="special">*</span> <span class="special">=</span> <span class="number">0</span> 143 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">enable_if_convertible</span><span class="special"><</span><span class="identifier">OIIter</span><span class="special">,</span> <span class="identifier">IndexIterator</span><span class="special">>::</span><span class="identifier">type</span><span class="special">*</span> <span class="special">=</span> <span class="number">0</span> 144 <span class="special">);</span> 145 <span class="identifier">reference</span> <span class="keyword">operator</span><span class="special">*()</span> <span class="keyword">const</span><span class="special">;</span> 146 <span class="identifier">permutation_iterator</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">++();</span> 147 <span class="identifier">ElementIterator</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">base</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span> 148<span class="keyword">private</span><span class="special">:</span> 149 <span class="identifier">ElementIterator</span> <span class="identifier">m_elt</span><span class="special">;</span> <span class="comment">// exposition only</span> 150 <span class="identifier">IndexIterator</span> <span class="identifier">m_order</span><span class="special">;</span> <span class="comment">// exposition only</span> 151<span class="special">};</span> 152 153<span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">ElementIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">IndexIterator</span><span class="special">></span> 154<span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">ElementIterator</span><span class="special">,</span> <span class="identifier">IndexIterator</span><span class="special">></span> 155<span class="identifier">make_permutation_iterator</span><span class="special">(</span> <span class="identifier">ElementIterator</span> <span class="identifier">e</span><span class="special">,</span> <span class="identifier">IndexIterator</span> <span class="identifier">i</span><span class="special">);</span> 156</pre> 157<h4> 158<a name="iterator.specialized.permutation.h3"></a> 159 <span class="phrase"><a name="iterator.specialized.permutation.requirements"></a></span><a class="link" href="permutation.html#iterator.specialized.permutation.requirements">Requirements</a> 160 </h4> 161<p> 162 <code class="computeroutput"><span class="identifier">ElementIterator</span></code> shall model 163 Random Access Traversal Iterator. <code class="computeroutput"><span class="identifier">IndexIterator</span></code> 164 shall model Readable Iterator. The value type of the <code class="computeroutput"><span class="identifier">IndexIterator</span></code> 165 must be convertible to the difference type of <code class="computeroutput"><span class="identifier">ElementIterator</span></code>. 166 </p> 167<h4> 168<a name="iterator.specialized.permutation.h4"></a> 169 <span class="phrase"><a name="iterator.specialized.permutation.concepts"></a></span><a class="link" href="permutation.html#iterator.specialized.permutation.concepts">Concepts</a> 170 </h4> 171<p> 172 <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> models 173 the same iterator traversal concepts as <code class="computeroutput"><span class="identifier">IndexIterator</span></code> 174 and the same iterator access concepts as <code class="computeroutput"><span class="identifier">ElementIterator</span></code>. 175 </p> 176<p> 177 If <code class="computeroutput"><span class="identifier">IndexIterator</span></code> models Single 178 Pass Iterator and <code class="computeroutput"><span class="identifier">ElementIterator</span></code> 179 models Readable Iterator then <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> 180 models Input Iterator. 181 </p> 182<p> 183 If <code class="computeroutput"><span class="identifier">IndexIterator</span></code> models Forward 184 Traversal Iterator and <code class="computeroutput"><span class="identifier">ElementIterator</span></code> 185 models Readable Lvalue Iterator then <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> 186 models Forward Iterator. 187 </p> 188<p> 189 If <code class="computeroutput"><span class="identifier">IndexIterator</span></code> models Bidirectional 190 Traversal Iterator and <code class="computeroutput"><span class="identifier">ElementIterator</span></code> 191 models Readable Lvalue Iterator then <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> 192 models Bidirectional Iterator. 193 </p> 194<p> 195 If <code class="computeroutput"><span class="identifier">IndexIterator</span></code> models Random 196 Access Traversal Iterator and <code class="computeroutput"><span class="identifier">ElementIterator</span></code> 197 models Readable Lvalue Iterator then <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> 198 models Random Access Iterator. 199 </p> 200<p> 201 <code class="computeroutput"><span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">E1</span><span class="special">,</span> <span class="identifier">X</span><span class="special">,</span> <span class="identifier">V1</span><span class="special">,</span> 202 <span class="identifier">C2</span><span class="special">,</span> <span class="identifier">R1</span><span class="special">,</span> <span class="identifier">D1</span><span class="special">></span></code> is interoperable with <code class="computeroutput"><span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">E2</span><span class="special">,</span> <span class="identifier">Y</span><span class="special">,</span> 203 <span class="identifier">V2</span><span class="special">,</span> <span class="identifier">C2</span><span class="special">,</span> <span class="identifier">R2</span><span class="special">,</span> <span class="identifier">D2</span><span class="special">></span></code> 204 if and only if <code class="computeroutput"><span class="identifier">X</span></code> is interoperable 205 with <code class="computeroutput"><span class="identifier">Y</span></code> and <code class="computeroutput"><span class="identifier">E1</span></code> is convertible to <code class="computeroutput"><span class="identifier">E2</span></code>. 206 </p> 207<h4> 208<a name="iterator.specialized.permutation.h5"></a> 209 <span class="phrase"><a name="iterator.specialized.permutation.operations"></a></span><a class="link" href="permutation.html#iterator.specialized.permutation.operations">Operations</a> 210 </h4> 211<p> 212 In addition to those operations required by the concepts that <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> models, <code class="computeroutput"><span class="identifier">permutation_iterator</span></code> provides the following 213 operations. 214 </p> 215<pre class="programlisting"><span class="identifier">permutation_iterator</span><span class="special">();</span> 216</pre> 217<p> 218 <span class="bold"><strong>Effects: </strong></span> Default constructs <code class="computeroutput"><span class="identifier">m_elt</span></code> and <code class="computeroutput"><span class="identifier">m_order</span></code>. 219 </p> 220<pre class="programlisting"><span class="keyword">explicit</span> <span class="identifier">permutation_iterator</span><span class="special">(</span><span class="identifier">ElementIterator</span> <span class="identifier">x</span><span class="special">,</span> <span class="identifier">IndexIterator</span> <span class="identifier">y</span><span class="special">);</span> 221</pre> 222<p> 223 <span class="bold"><strong>Effects: </strong></span> Constructs <code class="computeroutput"><span class="identifier">m_elt</span></code> 224 from <code class="computeroutput"><span class="identifier">x</span></code> and <code class="computeroutput"><span class="identifier">m_order</span></code> from <code class="computeroutput"><span class="identifier">y</span></code>. 225 </p> 226<pre class="programlisting"><span class="keyword">template</span><span class="special"><</span> <span class="keyword">class</span> <span class="identifier">OEIter</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">OIIter</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">V</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">C</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">R</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">D</span> <span class="special">></span> 227<span class="identifier">permutation_iterator</span><span class="special">(</span> 228 <span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">OEIter</span><span class="special">,</span> <span class="identifier">OIIter</span><span class="special">,</span> <span class="identifier">V</span><span class="special">,</span> <span class="identifier">C</span><span class="special">,</span> <span class="identifier">R</span><span class="special">,</span> <span class="identifier">D</span><span class="special">></span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">r</span> 229 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">enable_if_convertible</span><span class="special"><</span><span class="identifier">OEIter</span><span class="special">,</span> <span class="identifier">ElementIterator</span><span class="special">>::</span><span class="identifier">type</span><span class="special">*</span> <span class="special">=</span> <span class="number">0</span> 230 <span class="special">,</span> <span class="keyword">typename</span> <span class="identifier">enable_if_convertible</span><span class="special"><</span><span class="identifier">OIIter</span><span class="special">,</span> <span class="identifier">IndexIterator</span><span class="special">>::</span><span class="identifier">type</span><span class="special">*</span> <span class="special">=</span> <span class="number">0</span> 231<span class="special">);</span> 232</pre> 233<p> 234 <span class="bold"><strong>Effects: </strong></span> Constructs <code class="computeroutput"><span class="identifier">m_elt</span></code> 235 from <code class="computeroutput"><span class="identifier">r</span><span class="special">.</span><span class="identifier">m_elt</span></code> and <code class="computeroutput"><span class="identifier">m_order</span></code> 236 from <code class="computeroutput"><span class="identifier">y</span><span class="special">.</span><span class="identifier">m_order</span></code>. 237 </p> 238<pre class="programlisting"><span class="identifier">reference</span> <span class="keyword">operator</span><span class="special">*()</span> <span class="keyword">const</span><span class="special">;</span> 239</pre> 240<p> 241 <span class="bold"><strong>Returns: </strong></span> <code class="computeroutput"><span class="special">*(</span><span class="identifier">m_elt</span> <span class="special">+</span> <span class="special">*</span><span class="identifier">m_order</span><span class="special">)</span></code> 242 </p> 243<pre class="programlisting"><span class="identifier">permutation_iterator</span><span class="special">&</span> <span class="keyword">operator</span><span class="special">++();</span> 244</pre> 245<p> 246 <span class="bold"><strong>Effects: </strong></span> <code class="computeroutput"><span class="special">++</span><span class="identifier">m_order</span></code><br> <span class="bold"><strong>Returns: 247 </strong></span> <code class="computeroutput"><span class="special">*</span><span class="keyword">this</span></code> 248 </p> 249<pre class="programlisting"><span class="identifier">ElementIterator</span> <span class="keyword">const</span><span class="special">&</span> <span class="identifier">base</span><span class="special">()</span> <span class="keyword">const</span><span class="special">;</span> 250</pre> 251<p> 252 <span class="bold"><strong>Returns: </strong></span> <code class="computeroutput"><span class="identifier">m_order</span></code> 253 </p> 254<pre class="programlisting"><span class="keyword">template</span> <span class="special"><</span><span class="keyword">class</span> <span class="identifier">ElementIterator</span><span class="special">,</span> <span class="keyword">class</span> <span class="identifier">IndexIterator</span><span class="special">></span> 255<span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">ElementIterator</span><span class="special">,</span> <span class="identifier">IndexIterator</span><span class="special">></span> 256<span class="identifier">make_permutation_iterator</span><span class="special">(</span><span class="identifier">ElementIterator</span> <span class="identifier">e</span><span class="special">,</span> <span class="identifier">IndexIterator</span> <span class="identifier">i</span><span class="special">);</span> 257</pre> 258<p> 259 <span class="bold"><strong>Returns: </strong></span> <code class="computeroutput"><span class="identifier">permutation_iterator</span><span class="special"><</span><span class="identifier">ElementIterator</span><span class="special">,</span> <span class="identifier">IndexIterator</span><span class="special">>(</span><span class="identifier">e</span><span class="special">,</span> <span class="identifier">i</span><span class="special">)</span></code> 260 </p> 261</div> 262<table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr> 263<td align="left"></td> 264<td align="right"><div class="copyright-footer">Copyright © 2003, 2005 David Abrahams Jeremy Siek Thomas 265 Witt<p> 266 Distributed under the Boost Software License, Version 1.0. (See accompanying 267 file LICENSE_1_0.txt or copy at <ulink url="http://www.boost.org/LICENSE_1_0.txt"> 268 http://www.boost.org/LICENSE_1_0.txt </ulink>) 269 </p> 270</div></td> 271</tr></table> 272<hr> 273<div class="spirit-nav"> 274<a accesskey="p" href="indirect.html"><img src="../../../../../../doc/src/images/prev.png" alt="Prev"></a><a accesskey="u" href="../specialized.html"><img src="../../../../../../doc/src/images/up.png" alt="Up"></a><a accesskey="h" href="../../index.html"><img src="../../../../../../doc/src/images/home.png" alt="Home"></a><a accesskey="n" href="reverse.html"><img src="../../../../../../doc/src/images/next.png" alt="Next"></a> 275</div> 276</body> 277</html> 278
