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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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