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  24 </div>
  25 <div class="section boost_icl_examples_std_copy" lang="en">
  26 <div class="titlepage"><div><div><h3 class="title">
  27 <a name="boost_icl.examples.std_copy"></a><a class="link" href="std_copy.html" title="Std copy">Std copy</a>
  28 </h3></div></div></div>
  29 <p>
  30         The standard algorithm <a href="http://www.cplusplus.com/reference/algorithm/copy/" target="_top"><code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code></a>
  31         can be used to fill interval containers from standard containers of intervals
  32         or interval value pairs (segments). Because intervals do not represent <span class="emphasis"><em><span class="bold"><strong>elements</strong></span></em></span> but <span class="emphasis"><em><span class="bold"><strong>sets</strong></span></em></span>,
  33         that can be empty or contain more than one element, the usage of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code>
  34         differs from what we are familiar with using <span class="emphasis"><em>containers of elements</em></span>.
  35       </p>
  36 <div class="itemizedlist"><ul type="disc">
  37 <li>
  38           Use <code class="computeroutput"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">inserter</span></code> from <code class="computeroutput"><span class="preprocessor">#include</span>
  39           <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">icl</span><span class="special">/</span><span class="identifier">iterator</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span></code> instead of <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">inserter</span></code>
  40           to call insertions on the target interval container.
  41         </li>
  42 <li>
  43           As shown in the examples above and below this point, most of the time we
  44           will not be interested to <code class="computeroutput"><span class="identifier">insert</span></code>
  45           segments into <code class="computeroutput"><a class="link" href="../../boost/icl/interval_map.html" title="Class template interval_map">interval_maps</a></code>
  46           but to <a class="link" href="../function_reference/addition.html" title="Addition"><span class="emphasis"><em><span class="bold"><strong>add</strong></span></em></span></a> them, in order to generate
  47           the desired aggregation results. You can use <code class="computeroutput"><span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span></code>
  48           with an <code class="computeroutput"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">adder</span></code> instead of an <code class="computeroutput"><span class="identifier">icl</span><span class="special">::</span><span class="identifier">inserter</span></code>
  49           to achieve this.
  50         </li>
  51 </ul></div>
  52 <p>
  53         </p>
  54 <p>
  55
  56 </p>
  57 <pre class="programlisting"><span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">iostream</span><span class="special">&gt;</span>
  58 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">vector</span><span class="special">&gt;</span>
  59 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">algorithm</span><span class="special">&gt;</span>
  60 <span class="preprocessor">#include</span> <span class="special">&lt;</span><span class="identifier">boost</span><span class="special">/</span><span class="identifier">icl</span><span class="special">/</span><span class="identifier">interval_map</span><span class="special">.</span><span class="identifier">hpp</span><span class="special">&gt;</span>
  61
  62 <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">std</span><span class="special">;</span>
  63 <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">;</span>
  64 <span class="keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">icl</span><span class="special">;</span>
  65
  66 <span class="comment">// 'make_segments' returns a vector of interval value pairs, which
  67 </span><span class="comment">// are not sorted. The values are taken from the minimal example
  68 </span><span class="comment">// in section 'interval combining styles'.
  69 </span><span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;,</span> <span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">make_segments</span><span class="special">()</span>
  70 <span class="special">{</span>
  71     <span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;,</span> <span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">segment_vec</span><span class="special">;</span>
  72     <span class="identifier">segment_vec</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">right_open</span><span class="special">(</span><span class="number">2</span><span class="special">,</span><span class="number">4</span><span class="special">),</span> <span class="number">1</span><span class="special">));</span>
  73     <span class="identifier">segment_vec</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">right_open</span><span class="special">(</span><span class="number">4</span><span class="special">,</span><span class="number">5</span><span class="special">),</span> <span class="number">1</span><span class="special">));</span>
  74     <span class="identifier">segment_vec</span><span class="special">.</span><span class="identifier">push_back</span><span class="special">(</span><span class="identifier">make_pair</span><span class="special">(</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;::</span><span class="identifier">right_open</span><span class="special">(</span><span class="number">1</span><span class="special">,</span><span class="number">3</span><span class="special">),</span> <span class="number">1</span><span class="special">));</span>
  75     <span class="keyword">return</span> <span class="identifier">segment_vec</span><span class="special">;</span>
  76 <span class="special">}</span>
  77
  78 <span class="comment">// 'show_segments' displays the source segements.
  79 </span><span class="keyword">void</span> <span class="identifier">show_segments</span><span class="special">(</span><span class="keyword">const</span> <span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;,</span> <span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;&amp;</span> <span class="identifier">segments</span><span class="special">)</span>
  80 <span class="special">{</span>
  81     <span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;,</span> <span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;::</span><span class="identifier">const_iterator</span> <span class="identifier">iter</span> <span class="special">=</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">begin</span><span class="special">();</span>
  82     <span class="keyword">while</span><span class="special">(</span><span class="identifier">iter</span> <span class="special">!=</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">end</span><span class="special">())</span>
  83     <span class="special">{</span>
  84         <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"("</span> <span class="special">&lt;&lt;</span> <span class="identifier">iter</span><span class="special">-&gt;</span><span class="identifier">first</span> <span class="special">&lt;&lt;</span> <span class="string">","</span> <span class="special">&lt;&lt;</span> <span class="identifier">iter</span><span class="special">-&gt;</span><span class="identifier">second</span> <span class="special">&lt;&lt;</span> <span class="string">")"</span><span class="special">;</span>
  85         <span class="special">++</span><span class="identifier">iter</span><span class="special">;</span>
  86     <span class="special">}</span>
  87 <span class="special">}</span>
  88
  89 <span class="keyword">void</span> <span class="identifier">std_copy</span><span class="special">()</span>
  90 <span class="special">{</span>
  91     <span class="comment">// So we have some segments stored in an std container.
  92 </span>    <span class="identifier">vector</span><span class="special">&lt;</span><span class="identifier">pair</span><span class="special">&lt;</span><span class="identifier">discrete_interval</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">&gt;,</span> <span class="keyword">int</span><span class="special">&gt;</span> <span class="special">&gt;</span> <span class="identifier">segments</span> <span class="special">=</span> <span class="identifier">make_segments</span><span class="special">();</span>
  93     <span class="comment">// Display the input
  94 </span>    <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"input sequence: "</span><span class="special">;</span> <span class="identifier">show_segments</span><span class="special">(</span><span class="identifier">segments</span><span class="special">);</span> <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"\n\n"</span><span class="special">;</span>
  95
  96     <span class="comment">// We are going to 'std::copy' those segments into an interval_map:
  97 </span>    <span class="identifier">interval_map</span><span class="special">&lt;</span><span class="keyword">int</span><span class="special">,</span><span class="keyword">int</span><span class="special">&gt;</span> <span class="identifier">segmap</span><span class="special">;</span>
  98
  99     <span class="comment">// Use an 'icl::inserter' from &lt;boost/icl/iterator.hpp&gt; to call
 100 </span>    <span class="comment">// insertion on the interval container.
 101 </span>    <span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span><span class="identifier">segments</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span>
 102               <span class="identifier">icl</span><span class="special">::</span><span class="identifier">inserter</span><span class="special">(</span><span class="identifier">segmap</span><span class="special">,</span> <span class="identifier">segmap</span><span class="special">.</span><span class="identifier">end</span><span class="special">()));</span>
 103     <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"icl::inserting: "</span> <span class="special">&lt;&lt;</span> <span class="identifier">segmap</span> <span class="special">&lt;&lt;</span> <span class="identifier">endl</span><span class="special">;</span>
 104     <span class="identifier">segmap</span><span class="special">.</span><span class="identifier">clear</span><span class="special">();</span>
 105
 106     <span class="comment">// When we are feeding data into interval_maps, most of the time we are
 107 </span>    <span class="comment">// intending to compute an aggregation result. So we are not interested
 108 </span>    <span class="comment">// the std::insert semantincs but the aggregating icl::addition semantics.
 109 </span>    <span class="comment">// To achieve this there is an icl::add_iterator and an icl::adder function
 110 </span>    <span class="comment">// provided in &lt;boost/icl/iterator.hpp&gt;.
 111 </span>    <span class="identifier">std</span><span class="special">::</span><span class="identifier">copy</span><span class="special">(</span><span class="identifier">segments</span><span class="special">.</span><span class="identifier">begin</span><span class="special">(),</span> <span class="identifier">segments</span><span class="special">.</span><span class="identifier">end</span><span class="special">(),</span>
 112               <span class="identifier">icl</span><span class="special">::</span><span class="identifier">adder</span><span class="special">(</span><span class="identifier">segmap</span><span class="special">,</span> <span class="identifier">segmap</span><span class="special">.</span><span class="identifier">end</span><span class="special">()));</span> <span class="comment">//Aggregating associated values
 113 </span>    <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"icl::adding   : "</span> <span class="special">&lt;&lt;</span> <span class="identifier">segmap</span> <span class="special">&lt;&lt;</span> <span class="identifier">endl</span><span class="special">;</span>
 114
 115     <span class="comment">// In this last case, the semantics of 'std::copy' transforms to the
 116 </span>    <span class="comment">// generalized addition operation, that is implemented by operator
 117 </span>    <span class="comment">// += or + on itl maps and sets.
 118 </span><span class="special">}</span>
 119
 120 <span class="keyword">int</span> <span class="identifier">main</span><span class="special">()</span>
 121 <span class="special">{</span>
 122     <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"&gt;&gt;    Interval Container Library: Example std_copy.cpp    &lt;&lt;\n"</span><span class="special">;</span>
 123     <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"-----------------------------------------------------------\n"</span><span class="special">;</span>
 124     <span class="identifier">cout</span> <span class="special">&lt;&lt;</span> <span class="string">"Using std::copy to fill an interval_map:\n\n"</span><span class="special">;</span>
 125
 126     <span class="identifier">std_copy</span><span class="special">();</span>
 127     <span class="keyword">return</span> <span class="number">0</span><span class="special">;</span>
 128 <span class="special">}</span>
 129
 130 <span class="comment">// Program output:
 131 </span><span class="comment">/*---------------------------------------------------------
 132 &gt;&gt;    Interval Container Library: Example std_copy.cpp    &lt;&lt;
 133 -----------------------------------------------------------
 134 Using std::copy to fill an interval_map:
 135
 136 input sequence: ([2,4),1)([4,5),1)([1,3),1)
 137
 138 icl::inserting: {([1,5)-&gt;1)}
 139 icl::adding   : {([1,2)-&gt;1)([2,3)-&gt;2)([3,5)-&gt;1)}
 140 ---------------------------------------------------------*/</span>
 141 </pre>
 142 <p>
 143         </p>
 144 <p>
 145       </p>
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 147 <table xmlns:rev="http://www.cs.rpi.edu/~gregod/boost/tools/doc/revision" width="100%"><tr>
 148 <td align="left"></td>
 149 <td align="right"><div class="copyright-footer">Copyright &#169; 2007 -2010 Joachim Faulhaber<br>Copyright &#169; 1999 -2006 Cortex Software GmbH<p>
 150         Distributed under the Boost Software License, Version 1.0. (See accompanying
 151         file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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