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     <pre><span class=comment>//
 // Boost.Pointer Container
 //
 //  Copyright Thorsten Ottosen 2003-2005. Use, modification and
 //  distribution is subject to the Boost Software License, Version
 //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
 //  http://www.boost.org/LICENSE_1_0.txt)
 //
 // For more information, see http://www.boost.org/libs/ptr_container/
 //

 //
 // This example is intended to get you started.
 // Notice how the smart container
 //
 // 1. takes ownership of objects
 // 2. transfers ownership
 // 3. applies indirection to iterators
 // 4. clones objects from other smart containers
 //

 //
 // First we select which container to use.
 //</span>
 <span class=preprocessor>#include</span> <span class=special>&lt;</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>ptr_container</span><span class=special>/</span><span class=identifier>ptr_deque</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>&gt;</span>

 <span class=comment>//
 // we need these later in the example
 //</span>
 <span class=preprocessor>#include</span> <span class=special>&lt;</span><span class=identifier>boost</span><span class=special>/</span><span class=identifier>assert</span><span class=special>.</span><span class=identifier>hpp</span><span class=special>&gt;</span>
 <span class=preprocessor>#include</span> <span class=special>&lt;</span><span class=identifier>string</span><span class=special>&gt;</span>
 <span class=preprocessor>#include</span> <span class=special>&lt;</span><span class=identifier>exception</span><span class=special>&gt;</span>


 <span class=comment>//
 // Then we define a small polymorphic class
 // hierarchy.
 //</span>

 <span class=keyword>class</span> <span class=identifier>animal</span> <span class=special>:</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>noncopyable</span>
 <span class=special>{</span>
     <span class=keyword>virtual</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>do_speak</span><span class=special>()</span> <span class=keyword>const</span> <span class=special>=</span> <span class=number>0</span><span class=special>;</span>
     <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>name_</span><span class=special>;</span>

 <span class=keyword>protected</span><span class=special>:</span>
     <span class=comment>//
     // Animals cannot be copied...
     //</span>
     <span class=identifier>animal</span><span class=special>(</span> <span class=keyword>const</span> <span class=identifier>animal</span><span class=special>&amp;</span> <span class=identifier>r</span> <span class=special>)</span> <span class=special>:</span> <span class=identifier>name_</span><span class=special>(</span> <span class=identifier>r</span><span class=special>.</span><span class=identifier>name_</span> <span class=special>)</span>           <span class=special>{</span> <span class=special>}</span>
     <span class=keyword>void</span> <span class=keyword>operator</span><span class=special>=(</span> <span class=keyword>const</span> <span class=identifier>animal</span><span class=special>&amp;</span> <span class=special>);</span>

 <span class=keyword>private</span><span class=special>:</span>
     <span class=comment>//
     // ...but due to advances in genetics, we can clone them!
     //</span>

     <span class=keyword>virtual</span> <span class=identifier>animal</span><span class=special>*</span> <span class=identifier>do_clone</span><span class=special>()</span> <span class=keyword>const</span> <span class=special>=</span> <span class=number>0</span><span class=special>;</span>

 <span class=keyword>public</span><span class=special>:</span>
     <span class=identifier>animal</span><span class=special>(</span> <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span><span class=special>&amp;</span> <span class=identifier>name</span> <span class=special>)</span> <span class=special>:</span> <span class=identifier>name_</span><span class=special>(</span><span class=identifier>name</span><span class=special>)</span>        <span class=special>{</span> <span class=special>}</span>
     <span class=keyword>virtual</span> <span class=special>~</span><span class=identifier>animal</span><span class=special>()</span> <span class=keyword>throw</span><span class=special>()</span>                              <span class=special>{</span> <span class=special>}</span>

     <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>speak</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>do_speak</span><span class=special>();</span>
     <span class=special>}</span>

     <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>name</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>name_</span><span class=special>;</span>
     <span class=special>}</span>

     <span class=identifier>animal</span><span class=special>*</span> <span class=identifier>clone</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>do_clone</span><span class=special>();</span>
     <span class=special>}</span>
 <span class=special>};</span>

 <span class=comment>//
 // An animal is still not Clonable. We need this last hook.
 //
 // Notice that we pass the animal by const reference
 // and return by pointer.
 //</span>

 <span class=identifier>animal</span><span class=special>*</span> <span class=identifier>new_clone</span><span class=special>(</span> <span class=keyword>const</span> <span class=identifier>animal</span><span class=special>&amp;</span> <span class=identifier>a</span> <span class=special>)</span>
 <span class=special>{</span>
     <span class=keyword>return</span> <span class=identifier>a</span><span class=special>.</span><span class=identifier>clone</span><span class=special>();</span>
 <span class=special>}</span>

 <span class=comment>//
 // We do not need to define 'delete_clone()' since
 // since the default is to call the default 'operator delete()'.
 //</span>

 <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>muuuh</span> <span class=special>=</span> <span class=string>&quot;Muuuh!&quot;</span><span class=special>;</span>
 <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>oiink</span> <span class=special>=</span> <span class=string>&quot;Oiiink&quot;</span><span class=special>;</span>

 <span class=keyword>class</span> <span class=identifier>cow</span> <span class=special>:</span> <span class=keyword>public</span> <span class=identifier>animal</span>
 <span class=special>{</span>
     <span class=keyword>virtual</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>do_speak</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>muuuh</span><span class=special>;</span>
     <span class=special>}</span>

     <span class=keyword>virtual</span> <span class=identifier>animal</span><span class=special>*</span> <span class=identifier>do_clone</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=keyword>new</span> <span class=identifier>cow</span><span class=special>(</span> <span class=special>*</span><span class=keyword>this</span> <span class=special>);</span>
     <span class=special>}</span>

 <span class=keyword>public</span><span class=special>:</span>
     <span class=identifier>cow</span><span class=special>(</span> <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span><span class=special>&amp;</span> <span class=identifier>name</span> <span class=special>)</span> <span class=special>:</span> <span class=identifier>animal</span><span class=special>(</span><span class=identifier>name</span><span class=special>)</span>          <span class=special>{</span> <span class=special>}</span>
 <span class=special>};</span>

 <span class=keyword>class</span> <span class=identifier>pig</span> <span class=special>:</span> <span class=keyword>public</span> <span class=identifier>animal</span>
 <span class=special>{</span>
     <span class=keyword>virtual</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span> <span class=identifier>do_speak</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>oiink</span><span class=special>;</span>
     <span class=special>}</span>

     <span class=keyword>virtual</span> <span class=identifier>animal</span><span class=special>*</span> <span class=identifier>do_clone</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=keyword>new</span> <span class=identifier>pig</span><span class=special>(</span> <span class=special>*</span><span class=keyword>this</span> <span class=special>);</span>
     <span class=special>}</span>

 <span class=keyword>public</span><span class=special>:</span>
     <span class=identifier>pig</span><span class=special>(</span> <span class=keyword>const</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>string</span><span class=special>&amp;</span> <span class=identifier>name</span> <span class=special>)</span> <span class=special>:</span> <span class=identifier>animal</span><span class=special>(</span><span class=identifier>name</span><span class=special>)</span>          <span class=special>{</span> <span class=special>}</span>
 <span class=special>};</span>

 <span class=comment>//
 // Then we, of course, need a place to put all
 // those animals.
 //</span>

 <span class=keyword>class</span> <span class=identifier>farm</span>
 <span class=special>{</span>
     <span class=comment>//
     // This is where the smart containers are handy
     //</span>
     <span class=keyword>typedef</span> <span class=identifier>boost</span><span class=special>::</span><span class=identifier>ptr_deque</span><span class=special>&lt;</span><span class=identifier>animal</span><span class=special>&gt;</span> <span class=identifier>barn_type</span><span class=special>;</span>
     <span class=identifier>barn_type</span>                        <span class=identifier>barn</span><span class=special>;</span>

     <span class=comment>//
     // An error type
     //</span>
     <span class=keyword>struct</span> <span class=identifier>farm_trouble</span> <span class=special>:</span> <span class=keyword>public</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>exception</span>           <span class=special>{</span> <span class=special>};</span>

 <span class=keyword>public</span><span class=special>:</span>
     <span class=comment>//
     // We would like to make it possible to
     // iterate over the animals in the farm
     //</span>
     <span class=keyword>typedef</span> <span class=identifier>barn_type</span><span class=special>::</span><span class=identifier>iterator</span>  <span class=identifier>animal_iterator</span><span class=special>;</span>

     <span class=comment>//
     // We also need to count the farm's size...
     //</span>
     <span class=keyword>typedef</span> <span class=identifier>barn_type</span><span class=special>::</span><span class=identifier>size_type</span> <span class=identifier>size_type</span><span class=special>;</span>

     <span class=comment>//
     // And we also want to transfer an animal
     // safely around. The easiest way to think
     // about '::auto_type' is to imagine a simplified
     // 'std::auto_ptr&lt;T&gt;' ... this means you can expect
     //
     //   T* operator-&gt;()
     //   T* release()
     //   deleting destructor
     //
     // but not more.
     //</span>
     <span class=keyword>typedef</span> <span class=identifier>barn_type</span><span class=special>::</span><span class=identifier>auto_type</span>  <span class=identifier>animal_transport</span><span class=special>;</span>

     <span class=comment>//
     // Create an empty farm.
     //</span>
     <span class=identifier>farm</span><span class=special>()</span>                                                 <span class=special>{</span> <span class=special>}</span>

     <span class=comment>//
     // We need a constructor that can make a new
     // farm by cloning a range of animals.
     //</span>
     <span class=identifier>farm</span><span class=special>(</span> <span class=identifier>animal_iterator</span> <span class=identifier>begin</span><span class=special>,</span> <span class=identifier>animal_iterator</span> <span class=identifier>end</span> <span class=special>)</span>
      <span class=special>:</span>
         <span class=comment>//
         // Objects are always cloned before insertion
         // unless we explicitly add a pointer or
         // use 'release()'. Therefore we actually
         // clone all animals in the range
         //</span>
         <span class=identifier>barn</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=special>{</span> <span class=special>}</span>

     <span class=comment>//
     // ... so we need some other function too
     //</span>

     <span class=identifier>animal_iterator</span> <span class=identifier>begin</span><span class=special>()</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>barn</span><span class=special>.</span><span class=identifier>begin</span><span class=special>();</span>
     <span class=special>}</span>

     <span class=identifier>animal_iterator</span> <span class=identifier>end</span><span class=special>()</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>barn</span><span class=special>.</span><span class=identifier>end</span><span class=special>();</span>
     <span class=special>}</span>

     <span class=comment>//
     // Here it is quite ok to have an 'animal*' argument.
     // The smart container will handle all ownership
     // issues.
     //</span>
     <span class=keyword>void</span> <span class=identifier>buy_animal</span><span class=special>(</span> <span class=identifier>animal</span><span class=special>*</span> <span class=identifier>a</span> <span class=special>)</span>
     <span class=special>{</span>
         <span class=identifier>barn</span><span class=special>.</span><span class=identifier>push_back</span><span class=special>(</span> <span class=identifier>a</span> <span class=special>);</span>
     <span class=special>}</span>

     <span class=comment>//
     // The farm can also be in economical trouble and
     // therefore be in the need to sell animals.
     //</span>
     <span class=identifier>animal_transport</span> <span class=identifier>sell_animal</span><span class=special>(</span> <span class=identifier>animal_iterator</span> <span class=identifier>to_sell</span> <span class=special>)</span>
     <span class=special>{</span>
         <span class=keyword>if</span><span class=special>(</span> <span class=identifier>to_sell</span> <span class=special>==</span> <span class=identifier>end</span><span class=special>()</span> <span class=special>)</span>
             <span class=keyword>throw</span> <span class=identifier>farm_trouble</span><span class=special>();</span>

         <span class=comment>//
         // Here we remove the animal from the barn,
         // but the animal is not deleted yet...it's
         // up to the buyer to decide what
         // to do with it.
         //</span>
         <span class=keyword>return</span> <span class=identifier>barn</span><span class=special>.</span><span class=identifier>release</span><span class=special>(</span> <span class=identifier>to_sell</span> <span class=special>);</span>
     <span class=special>}</span>

     <span class=comment>//
     // How big a farm do we have?
     //</span>
     <span class=identifier>size_type</span> <span class=identifier>size</span><span class=special>()</span> <span class=keyword>const</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>barn</span><span class=special>.</span><span class=identifier>size</span><span class=special>();</span>
     <span class=special>}</span>

     <span class=comment>//
     // If things are bad, we might choose to sell all animals :-(
     //</span>
     <span class=identifier>std</span><span class=special>::</span><span class=identifier>auto_ptr</span><span class=special>&lt;</span><span class=identifier>barn_type</span><span class=special>&gt;</span> <span class=identifier>sell_farm</span><span class=special>()</span>
     <span class=special>{</span>
         <span class=keyword>return</span> <span class=identifier>barn</span><span class=special>.</span><span class=identifier>release</span><span class=special>();</span>
     <span class=special>}</span>

     <span class=comment>//
     // However, if things are good, we might buy somebody
     // else's farm :-)
     //</span>

     <span class=keyword>void</span> <span class=identifier>buy_farm</span><span class=special>(</span> <span class=identifier>std</span><span class=special>::</span><span class=identifier>auto_ptr</span><span class=special>&lt;</span><span class=identifier>barn_type</span><span class=special>&gt;</span> <span class=identifier>other</span> <span class=special>)</span>
     <span class=special>{</span>
         <span class=comment>//
         // This line inserts all the animals from 'other'
         // and is guaranteed either to succeed or to have no
         // effect
         //</span>
         <span class=identifier>barn</span><span class=special>.</span><span class=identifier>transfer</span><span class=special>(</span> <span class=identifier>barn</span><span class=special>.</span><span class=identifier>end</span><span class=special>(),</span> <span class=comment>// insert new animals at the end</span>
                          <span class=special>*</span><span class=identifier>other</span> <span class=special>);</span>     <span class=comment>// we want to transfer all animals,
                                        // so we use the whole container as argument
         //
         // You might think you would have to do
         //
         // other.release();
         //
         // but '*other' is empty and can go out of scope as it wants
         //</span>
         <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>other</span><span class=special>-&gt;</span><span class=identifier>empty</span><span class=special>()</span> <span class=special>);</span>
     <span class=special>}</span>

 <span class=special>};</span> <span class=comment>// class 'farm'.</span>

 <span class=keyword>int</span> <span class=identifier>main</span><span class=special>()</span>
 <span class=special>{</span>
     <span class=comment>//
     // First we make a farm
     //</span>
     <span class=identifier>farm</span> <span class=identifier>animal_farm</span><span class=special>;</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span> <span class=special>==</span> <span class=number>0u</span> <span class=special>);</span>

     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=keyword>new</span> <span class=identifier>pig</span><span class=special>(</span><span class=string>&quot;Betty&quot;</span><span class=special>)</span> <span class=special>);</span>
     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=keyword>new</span> <span class=identifier>pig</span><span class=special>(</span><span class=string>&quot;Benny&quot;</span><span class=special>)</span> <span class=special>);</span>
     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=keyword>new</span> <span class=identifier>pig</span><span class=special>(</span><span class=string>&quot;Jeltzin&quot;</span><span class=special>)</span> <span class=special>);</span>
     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=keyword>new</span> <span class=identifier>cow</span><span class=special>(</span><span class=string>&quot;Hanz&quot;</span><span class=special>)</span> <span class=special>);</span>
     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=keyword>new</span> <span class=identifier>cow</span><span class=special>(</span><span class=string>&quot;Mary&quot;</span><span class=special>)</span> <span class=special>);</span>
     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=keyword>new</span> <span class=identifier>cow</span><span class=special>(</span><span class=string>&quot;Frederik&quot;</span><span class=special>)</span> <span class=special>);</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span> <span class=special>==</span> <span class=number>6u</span> <span class=special>);</span>

     <span class=comment>//
     // Then we make another farm...it will actually contain
     // a clone of the other farm.
     //</span>
     <span class=identifier>farm</span> <span class=identifier>new_farm</span><span class=special>(</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>begin</span><span class=special>(),</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>end</span><span class=special>()</span> <span class=special>);</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>new_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span> <span class=special>==</span> <span class=number>6u</span> <span class=special>);</span>

     <span class=comment>//
     // Is it really clones in the new farm?
     //</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>new_farm</span><span class=special>.</span><span class=identifier>begin</span><span class=special>()-&gt;</span><span class=identifier>name</span><span class=special>()</span> <span class=special>==</span> <span class=string>&quot;Betty&quot;</span> <span class=special>);</span>

     <span class=comment>//
     // Then we search for an animal, Mary (the Crown Princess of Denmark),
     // because we would like to buy her ...
     //</span>
     <span class=keyword>typedef</span> <span class=identifier>farm</span><span class=special>::</span><span class=identifier>animal_iterator</span> <span class=identifier>iterator</span><span class=special>;</span>
     <span class=identifier>iterator</span> <span class=identifier>to_sell</span><span class=special>;</span>
     <span class=keyword>for</span><span class=special>(</span> <span class=identifier>iterator</span> <span class=identifier>i</span>   <span class=special>=</span> <span class=identifier>animal_farm</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>animal_farm</span><span class=special>.</span><span class=identifier>end</span><span class=special>();</span>
          <span class=identifier>i</span> <span class=special>!=</span> <span class=identifier>end</span><span class=special>;</span> <span class=special>++</span><span class=identifier>i</span> <span class=special>)</span>
     <span class=special>{</span>
         <span class=keyword>if</span><span class=special>(</span> <span class=identifier>i</span><span class=special>-&gt;</span><span class=identifier>name</span><span class=special>()</span> <span class=special>==</span> <span class=string>&quot;Mary&quot;</span> <span class=special>)</span>
         <span class=special>{</span>
             <span class=identifier>to_sell</span> <span class=special>=</span> <span class=identifier>i</span><span class=special>;</span>
             <span class=keyword>break</span><span class=special>;</span>
         <span class=special>}</span>
     <span class=special>}</span>

     <span class=identifier>farm</span><span class=special>::</span><span class=identifier>animal_transport</span> <span class=identifier>mary</span> <span class=special>=</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>sell_animal</span><span class=special>(</span> <span class=identifier>to_sell</span> <span class=special>);</span>


     <span class=keyword>if</span><span class=special>(</span> <span class=identifier>mary</span><span class=special>-&gt;</span><span class=identifier>speak</span><span class=special>()</span> <span class=special>==</span> <span class=identifier>muuuh</span> <span class=special>)</span>
         <span class=comment>//
         // Great, Mary is a cow, and she may live longer
         //</span>
         <span class=identifier>new_farm</span><span class=special>.</span><span class=identifier>buy_animal</span><span class=special>(</span> <span class=identifier>mary</span><span class=special>.</span><span class=identifier>release</span><span class=special>()</span> <span class=special>);</span>
     <span class=keyword>else</span>
         <span class=comment>//
         // Then the animal would be destroyed (!)
         // when we go out of scope.
         //</span>
         <span class=special>;</span>

     <span class=comment>//
     // Now we can observe some changes to the two farms...
     //</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span> <span class=special>==</span> <span class=number>5u</span> <span class=special>);</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>new_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span>    <span class=special>==</span> <span class=number>7u</span> <span class=special>);</span>

     <span class=comment>//
     // The new farm has however underestimated how much
     // it cost to feed Mary and its owner is forced to sell the farm...
     //</span>
     <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>buy_farm</span><span class=special>(</span> <span class=identifier>new_farm</span><span class=special>.</span><span class=identifier>sell_farm</span><span class=special>()</span> <span class=special>);</span>

     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>new_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span>    <span class=special>==</span> <span class=number>0u</span> <span class=special>);</span>
     <span class=identifier>BOOST_ASSERT</span><span class=special>(</span> <span class=identifier>animal_farm</span><span class=special>.</span><span class=identifier>size</span><span class=special>()</span> <span class=special>==</span> <span class=number>12u</span> <span class=special>);</span>
 <span class=special>}</span>
 </pre>
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