293 lines
28 KiB
HTML
293 lines
28 KiB
HTML
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<title>std::operator+(std::basic_string)</title>
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<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_string_basic_string_operator skin-cppreference2 action-view cpp-navbar">
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<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>operator+<small>(std::basic_string)</small></h1>
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<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-string.html">string</a>‎ | <a href="cpp-string-basic_string.html">basic string</a></span></div>
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<div>定义于头文件 <code><a href="cpp-header-string.html"><string></a></code></div>
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<td></td>
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<td></td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> lhs,<br /></p>
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<span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(1)</td>
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<td><span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> lhs,<br /></p>
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<span class="kw4">const</span> CharT<span class="sy2">*</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(2)</td>
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<td><span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc<span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> lhs,<br /></p>
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CharT rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(3)</td>
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<td><span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> lhs,<br /></p>
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<span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(4)</td>
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<td><span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> CharT lhs,<br /></p>
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<span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(5)</td>
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<td><span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> lhs,<br /></p>
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<a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(6)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> lhs,<br /></p>
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<span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(7)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> lhs,<br /></p>
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<span class="kw4">const</span> CharT<span class="sy2">*</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(8)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> lhs,<br /></p>
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CharT rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(9)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&</span> lhs,<br /></p>
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<a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(10)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> <span class="kw4">const</span> CharT<span class="sy2">*</span> lhs,<br /></p>
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<a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(11)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl t-since-cxx11">
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<td>
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<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> CharT, <span class="kw1">class</span> Traits, <span class="kw1">class</span> Alloc <span class="sy1">></span><br /></span>
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<p> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><br />
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operator<span class="sy2">+</span><span class="br0">(</span> CharT lhs,<br /></p>
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<a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span>CharT,Traits,Alloc<span class="sy1">></span><span class="sy3">&&</span> rhs <span class="br0">)</span><span class="sy4">;</span></div>
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</td>
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<td>(12)</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span><br />
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<span class="t-mark">(C++20 起为 <code>constexpr</code>)</span></td>
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</tr>
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<tr class="t-dcl-sep">
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<td></td>
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<td></td>
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<td></td>
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</tr>
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</tbody>
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</table>
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<p>返回含有来自 <code>lhs</code> 的字符后随来自 <code>rhs</code> 的字符的字符串。</p>
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<table class="t-rev-begin">
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<tr class="t-rev t-since-cxx11">
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<td>
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<p>结果所用的分配器为：</p>
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<div class="t-li1"><span class="t-li">1-3)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-allocator_traits.html"><span class="kw701">std::<span class="me2">allocator_traits</span></span></a><span class="sy1"><</span>Alloc<span class="sy1">></span><span class="sy4">::</span><span class="me2">select_on_container_copy_construction</span><span class="br0">(</span>lhs.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span></div>
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<div class="t-li1"><span class="t-li">4-5)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-memory-allocator_traits.html"><span class="kw701">std::<span class="me2">allocator_traits</span></span></a><span class="sy1"><</span>Alloc<span class="sy1">></span><span class="sy4">::</span><span class="me2">select_on_container_copy_construction</span><span class="br0">(</span>rhs.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span></span></span></div>
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<div class="t-li1"><span class="t-li">6-9)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">lhs.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span></span></span></div>
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<div class="t-li1"><span class="t-li">10-12)</span> <span class="t-c"><span class="mw-geshi cpp source-cpp">rhs.<span class="me1">get_allocator</span><span class="br0">(</span><span class="br0">)</span></span></span></div>
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<p>换言之，若运算数之一是 <code>basic_string</code> 右值，则使用其分配器；否则在左值 <code>basic_string</code> 运算数的分配上使用 <code>select_on_container_copy_construction</code> 。每种情况下，当两者是拥有同一值类别的 <code>basic_string</code> 时，偏向左运算数。</p>
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<p><span class="t-v">(6-12)</span> 将所有右值 <code>basic_string</code> 运算数置于合法但未指定的状态。</p>
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</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
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<table class="t-par-begin">
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<tr class="t-par">
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<td>lhs</td>
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<td>-</td>
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<td><code>string</code> 、字符或指向空终止字符序列首字符的指针</td>
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</tr>
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<tr class="t-par">
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<td>rhs</td>
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<td>-</td>
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<td><code>string</code> 、字符或指向空终止字符序列首字符的指针</td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
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<p>含有来自 <code>lhs</code> 的字符后随来自 <code>rhs</code> 的字符的字符串<span class="t-rev-inl t-since-cxx11"><span>，使用指定如上的分配器</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></span></span>。</p>
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<table class="t-rev-begin">
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<tr class="t-rev t-since-cxx11">
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<td>
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<h3><span class="mw-headline" id=".E6.B3.A8.E8.A7.A3">注解</span></h3>
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<p>涉及有状态分配器时<span class="t-rev-inl t-since-cxx17"><span>（例如用 <span class="t-lc"><a href="cpp-string-basic_string.html">std::pmr::string</a></span> 时）</span> <span><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></span></span>，应该谨慎使用 <code>operator+</code> 。在 <a rel="nofollow" class="external text" href="https://wg21.link/P1165R1">P1165R1</a> 前，确定结果所用的分配器是历史事故，而且能在重载间无显著理由地变化。另外，对于 <span class="t-v">(1-5)</span> ，分配器传播行为在主流标准库实现间各异，且异于标准所描述的行为。</p>
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<p><code>operator+</code> 的结果所用的分配器对值类别敏感，故 <code>operator+</code> 相对于分配器传播不满足结合律：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1"><span class="kw1">using</span> my_string <span class="sy1">=</span> <a href="cpp-string-basic_string.html"><span class="kw1228">std::<span class="me2">basic_string</span></span></a><span class="sy1"><</span><span class="kw4">char</span>, <a href="cpp-string-char_traits.html"><span class="kw1267">std::<span class="me2">char_traits</span></span></a><span class="sy1"><</span><span class="kw4">char</span><span class="sy1">></span>, my_allocator<span class="sy1"><</span><span class="kw4">char</span><span class="sy1">>></span><span class="sy4">;</span>
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my_string cat<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
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<span class="kw4">const</span> my_string<span class="sy3">&</span> dog<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
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my_string meow <span class="sy1">=</span> <span class="coMULTI">/* ... */</span>, woof <span class="sy1">=</span> <span class="coMULTI">/* ... */</span><span class="sy4">;</span>
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meow <span class="sy2">+</span> cat<span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> <span class="coMULTI">/*...*/</span><span class="sy4">;</span> <span class="co1">// 使用 meow 的分配器上的 select_on_container_copy_construction</span>
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woof <span class="sy2">+</span> dog<span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> <span class="coMULTI">/*...*/</span><span class="sy4">;</span> <span class="co1">// 转而使用 dog() 的返回值的分配器</span>
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meow <span class="sy2">+</span> woof <span class="sy2">+</span> meow<span class="sy4">;</span> <span class="co1">// 使用 meow 的分配器上的 SOCCC</span>
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meow <span class="sy2">+</span> <span class="br0">(</span>woof <span class="sy2">+</span> meow<span class="br0">)</span><span class="sy4">;</span> <span class="co1">// 转而使用 woof 的分配器上的 select_on_container_copy_construction</span></pre></div>
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</div>
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<p>对于 <code>operator+</code> 链的调用，可通过前置拥有所欲分配器的右值 <code>basic_string</code> 控制最终结果所用的分配器：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1"><span class="co1">// 令最终结果使用 my_favorite_allocator</span>
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my_string<span class="br0">(</span>my_favorite_allocator<span class="br0">)</span> <span class="sy2">+</span> meow <span class="sy2">+</span> woof <span class="sy2">+</span> cat<span class="br0">(</span><span class="br0">)</span> <span class="sy2">+</span> dog<span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span></pre></div>
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</div>
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<p>为了在分配器上更好且可移植地控制，应该在以所欲分配器构造的结果字符串上，使用 <a href="cpp-string-basic_string-append.html"><code>append()</code></a> 、 <a href="cpp-string-basic_string-insert.html"><code>insert()</code></a> 及 <a href="cpp-string-basic_string-operator+=.html"><code>operator+=()</code></a> 之类的成员函数。</p>
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</td>
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<td><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
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<div class="t-example">
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<div class="t-example-live-link"></div>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="cpp source-cpp">
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<pre class="de1"><span class="co2">#include <iostream></span>
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<span class="co2">#include <string></span>
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<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
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<span class="br0">{</span>
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<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s1 <span class="sy1">=</span> <span class="st0">"Hello"</span><span class="sy4">;</span>
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<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> s2 <span class="sy1">=</span> <span class="st0">"world"</span><span class="sy4">;</span>
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<a href="cpp-io-cout.html"><span class="kw1758">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> s1 <span class="sy2">+</span> <span class="st0">' '</span> <span class="sy2">+</span> s2 <span class="sy2">+</span> <span class="st0">"!<span class="es1">\n</span>"</span><span class="sy4">;</span>
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<span class="br0">}</span></pre></div>
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</div>
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<p>输出：</p>
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<div dir="ltr" class="mw-geshi" style="text-align: left;">
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<div class="text source-text">
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<pre class="de1">Hello world!</pre></div>
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</div>
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</div>
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<h3><span class="mw-headline" id=".E7.BC.BA.E9.99.B7.E6.8A.A5.E5.91.8A">缺陷报告</span></h3>
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<p>下列更改行为的缺陷报告追溯地应用于以前出版的 C++ 标准。</p>
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<table class="dsctable" style="font-size:0.8em">
|
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<tr>
|
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<th>DR</th>
|
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<th>应用于</th>
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<th>出版时的行为</th>
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<th>正确行为</th>
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</tr>
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<tr>
|
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<td><a rel="nofollow" class="external text" href="https://wg21.link/P1165R1">P1165R1</a></td>
|
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<td>C++11</td>
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<td>分配器传播混乱且不一致</td>
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<td>使之更为一致</td>
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</tr>
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</table>
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<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
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<table class="t-dsc-begin">
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<tr class="t-dsc">
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<td>
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<div class="t-dsc-member-div">
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<div><a href="cpp-string-basic_string-operator+=.html"><span class="t-lines"><span>operator+=</span></span></a></div>
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</div>
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</td>
|
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<td>后附字符到结尾<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
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</tr>
|
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<tr class="t-dsc">
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<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-basic_string-append.html"><span class="t-lines"><span>append</span></span></a></div>
|
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</div>
|
|
</td>
|
|
<td>后附字符到结尾<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
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</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-string-basic_string-insert.html"><span class="t-lines"><span>insert</span></span></a></div>
|
|
</div>
|
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</td>
|
|
<td>插入字符<br />
|
|
<span class="t-mark">(公开成员函数)</span></td>
|
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</tr>
|
|
</table>
|
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</div>
|
|
<div class="visualClear"></div>
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</div>
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</div>
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</div>
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</body>
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</html>
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