454 lines
35 KiB
HTML
454 lines
35 KiB
HTML
<!DOCTYPE html>
|
|
<html lang="zh" dir="ltr" class="client-nojs" xmlns="http://www.w3.org/1999/xhtml" xml:lang="zh">
|
|
<head><meta http-equiv="x-ua-compatible" content="ie=edge">
|
|
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
|
|
<title>std::search</title>
|
|
<link rel="stylesheet" href="ext.css" />
|
|
<link rel="stylesheet" href="site_modules.css" />
|
|
</head>
|
|
<body class="mediawiki ltr sitedir-ltr ns-0 ns-subject page-cpp_algorithm_search skin-cppreference2 action-view cpp-navbar">
|
|
<div id="cpp-content-base">
|
|
<div id="content"><a id="top"></a>
|
|
<h1 id="firstHeading" class="firstHeading"><span style="font-size:0.7em; line-height:130%">std::</span>search</h1>
|
|
<div id="bodyContent">
|
|
<div id="contentSub"><span class="subpages">< <a href="cpp.html">cpp</a>‎ | <a href="cpp-algorithm.html">algorithm</a></span></div>
|
|
<div id="mw-content-text" lang="zh" dir="ltr" class="mw-content-ltr" xml:lang="zh">
|
|
<table class="t-dcl-begin">
|
|
<tbody>
|
|
<tr class="t-dsc-header">
|
|
<td>
|
|
<div>定义于头文件 <code><a href="cpp-header-algorithm.html"><algorithm></a></code></div>
|
|
</td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(1)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2 <span class="sy1">></span><br /></span>
|
|
<p>ForwardIt1 search<span class="br0">(</span> ForwardIt1 first, ForwardIt1 last,<br /></p>
|
|
ForwardIt2 s_first, ForwardIt2 s_last <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2 <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> ForwardIt1 search<span class="br0">(</span> ForwardIt1 first, ForwardIt1 last,<br /></p>
|
|
ForwardIt2 s_first, ForwardIt2 s_last <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl t-since-cxx17">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> ExecutionPolicy, <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2 <span class="sy1">></span><br /></span>
|
|
<p>ForwardIt1 search<span class="br0">(</span> ExecutionPolicy<span class="sy3">&&</span> policy, ForwardIt1 first, ForwardIt1 last,<br /></p>
|
|
ForwardIt2 s_first, ForwardIt2 s_last <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td>(2)</td>
|
|
<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(3)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2, <span class="kw1">class</span> BinaryPredicate <span class="sy1">></span><br /></span>
|
|
<p>ForwardIt1 search<span class="br0">(</span> ForwardIt1 first, ForwardIt1 last,<br /></p>
|
|
ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2, <span class="kw1">class</span> BinaryPredicate <span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> ForwardIt1 search<span class="br0">(</span> ForwardIt1 first, ForwardIt1 last,<br /></p>
|
|
ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl t-since-cxx17">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span> <span class="kw1">class</span> ExecutionPolicy, <span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2, <span class="kw1">class</span> BinaryPredicate <span class="sy1">></span><br /></span>
|
|
<p>ForwardIt1 search<span class="br0">(</span> ExecutionPolicy<span class="sy3">&&</span> policy, ForwardIt1 first, ForwardIt1 last,<br /></p>
|
|
ForwardIt2 s_first, ForwardIt2 s_last, BinaryPredicate p <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td>(4)</td>
|
|
<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody class="t-dcl-rev t-dcl-rev-num">
|
|
<tr class="t-dcl-rev-aux">
|
|
<td></td>
|
|
<td rowspan="142">(5)</td>
|
|
<td></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx17 t-until-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> ForwardIt, <span class="kw1">class</span> Searcher<span class="sy1">></span><br /></span>
|
|
<p>ForwardIt search<span class="br0">(</span> ForwardIt first, ForwardIt last,<br /></p>
|
|
<span class="kw4">const</span> Searcher<span class="sy3">&</span> searcher <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span><br />
|
|
<span class="t-mark-rev t-until-cxx20">(C++20 前)</span></td>
|
|
</tr>
|
|
<tr class="t-dcl t-since-cxx20">
|
|
<td>
|
|
<div><span class="mw-geshi cpp source-cpp"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> ForwardIt, <span class="kw1">class</span> Searcher<span class="sy1">></span><br /></span>
|
|
<p><span class="kw4">constexpr</span> ForwardIt search<span class="br0">(</span> ForwardIt first, ForwardIt last,<br /></p>
|
|
<span class="kw4">const</span> Searcher<span class="sy3">&</span> searcher <span class="br0">)</span><span class="sy4">;</span></div>
|
|
</td>
|
|
<td class="t-dcl-nopad"></td>
|
|
<td><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></td>
|
|
</tr>
|
|
</tbody>
|
|
<tbody>
|
|
<tr class="t-dcl-sep">
|
|
<td></td>
|
|
<td></td>
|
|
<td></td>
|
|
</tr>
|
|
</tbody>
|
|
</table>
|
|
<div class="t-li1"><span class="t-li">1-4)</span> 搜索范围 <code>[first, last - (s_last - s_first))</code> 中元素子序列 <code>[s_first, s_last)</code> 的首次出现。</div>
|
|
<div class="t-li2"><span class="t-li">1)</span> 元素用 <code>operator==</code> 比较。</div>
|
|
<div class="t-li2"><span class="t-li">3)</span> 元素用给定的二元谓词 <code>p</code> 比较。</div>
|
|
<div class="t-li2"><span class="t-li">2,4)</span> 同 <span class="t-v">(1,3)</span> ，但按 <code>policy</code> 执行。这些重载仅若 <span class="t-rev-inl t-until-cxx20"><span><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-algorithm-is_execution_policy.html"><span class="kw1564">std::<span class="me2">is_execution_policy_v</span></span></a><span class="sy1"><</span><a href="cpp-types-decay.html"><span class="kw629">std::<span class="me2">decay_t</span></span></a><span class="sy1"><</span>ExecutionPolicy<span class="sy1">>></span></span></span></span> <span><span class="t-mark-rev t-until-cxx20">(C++20 前)</span></span></span><span class="t-rev-inl t-since-cxx20"><span><span class="t-c"><span class="mw-geshi cpp source-cpp"><a href="cpp-algorithm-is_execution_policy.html"><span class="kw1564">std::<span class="me2">is_execution_policy_v</span></span></a><span class="sy1"><</span>std<span class="sy4">::</span><span class="me2">remove_cvref_t</span><span class="sy1"><</span>ExecutionPolicy<span class="sy1">>></span></span></span></span> <span><span class="t-mark-rev t-since-cxx20">(C++20 起)</span></span></span> 为 true 才参与重载决议。</div>
|
|
<div class="t-li1"><span class="t-li">5)</span> 在序列 <span class="texhtml" style="white-space: nowrap;">[first, last)</span> 中搜索 <code>searcher</code> 构造函数中指定的模式。等效地执行 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw1">return</span> searcher<span class="br0">(</span>first, last<span class="br0">)</span>.<span class="me1">first</span><span class="sy4">;</span></span></span> 。<a href="https://zh.cppreference.com/mwiki/index.php?title=cpp/named_req/Searcher&action=edit&redlink=1" class="new" title="cpp/named req/Searcher（页面不存在）"><span style="font-style:italic">搜索器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(Searcher)</span></a> 不必为<a href="cpp-named_req-CopyConstructible.html"><span style="font-style:italic">可复制构造</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(CopyConstructible)</span></a> 。</div>
|
|
<table class="t-rev-begin">
|
|
<tr class="t-rev t-since-cxx17">
|
|
<td>
|
|
<p>标准库提供下列搜索器：</p>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-default_searcher.html"><span class="t-lines"><span>default_searcher</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>标准 C++ 库搜索算法实现<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-boyer_moore_searcher.html"><span class="t-lines"><span>boyer_moore_searcher</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>Boyer-Moore 搜索算法实现<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-boyer_moore_horspool_searcher.html"><span class="t-lines"><span>boyer_moore_horspool_searcher</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>Boyer-Moore-Horspool 搜索算法实现<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</td>
|
|
<td><span class="t-mark-rev t-since-cxx17">(C++17 起)</span></td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E6.95.B0">参数</span></h3>
|
|
<table class="t-par-begin">
|
|
<tr class="t-par">
|
|
<td>first, last</td>
|
|
<td>-</td>
|
|
<td>要检验的元素范围</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>s_first, s_last</td>
|
|
<td>-</td>
|
|
<td>要搜索的元素范围</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>policy</td>
|
|
<td>-</td>
|
|
<td>所用的执行策略。细节见<a href="cpp-algorithm-execution_policy_tag_t.html">执行策略</a>。</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>searcher</td>
|
|
<td>-</td>
|
|
<td>封装搜索算法和搜索模式的搜索器</td>
|
|
</tr>
|
|
<tr class="t-par">
|
|
<td>p</td>
|
|
<td>-</td>
|
|
<td>若元素应被当做相等则返回 ​<span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw2">true</span></span></span> 的二元谓词。<br />
|
|
<p>谓词函数的签名应等价于如下：</p>
|
|
<p><span class="t-cc"><span class="mw-geshi cpp source-cpp"> <span class="kw4">bool</span> pred<span class="br0">(</span><span class="kw4">const</span> Type1 <span class="sy3">&</span>a, <span class="kw4">const</span> Type2 <span class="sy3">&</span>b<span class="br0">)</span><span class="sy4">;</span></span></span></p>
|
|
<p>虽然签名不必有 <span class="t-c"><span class="mw-geshi cpp source-cpp"><span class="kw4">const</span> <span class="sy3">&</span></span></span> ，函数也不能修改传递给它的对象，而且必须接受（可为 const 的）类型 <code>Type1</code> 与 <code>Type2</code> 的值，无关乎<a href="cpp-language-value_category.html">值类别</a>（从而不允许 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1 <span class="sy3">&</span></span></span> <span class="t-rev-inl t-since-cxx11"><span>，亦不允许 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1</span></span> ，除非 <code>Type1</code> 的移动等价于复制</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></span></span>）。<br />
|
|
类型 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1</span></span> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type2</span></span> 必须使得 <span class="t-c"><span class="mw-geshi cpp source-cpp">ForwardIt1</span></span> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">ForwardIt2</span></span> 类型的对象在解引用后分别能隐式转换到 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type1</span></span> 与 <span class="t-c"><span class="mw-geshi cpp source-cpp">Type2</span></span> 。 ​</p>
|
|
</td>
|
|
</tr>
|
|
<tr class="t-par-hitem">
|
|
<td colspan="3">类型要求</td>
|
|
</tr>
|
|
<tr class="t-par-req">
|
|
<td colspan="3">-
|
|
<div class="spacer"></div>
|
|
<code>ForwardIt1, ForwardIt2</code> 必须满足<a href="cpp-named_req-ForwardIterator.html"><span style="font-style:italic">老式向前迭代器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(LegacyForwardIterator)</span></a> 的要求。</td>
|
|
</tr>
|
|
<tr class="t-par-req">
|
|
<td colspan="3">-
|
|
<div class="spacer"></div>
|
|
<code>Searcher</code> 必须满足<a href="https://zh.cppreference.com/mwiki/index.php?title=cpp/named_req/Searcher&action=edit&redlink=1" class="new" title="cpp/named req/Searcher（页面不存在）"><span style="font-style:italic">搜索器</span> <span style="font-family: Georgia, 'DejaVu Serif', serif; font-style:italic">(Searcher)</span></a> 的要求。</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E8.BF.94.E5.9B.9E.E5.80.BC">返回值</span></h3>
|
|
<div class="t-li1"><span class="t-li">1-4)</span> 指向范围中 <code>[first, last - (s_last - s_first))</code> ，首个子序列 <code>[s_first, s_last)</code> 起始的迭代器。若找不到这种子序列，则返回 <code>last</code> 。<br />
|
|
<span class="t-rev-inl t-since-cxx11"><span>若 <code>[s_first, s_last)</code> 为空，则返回 <code>first</code> 。</span> <span><span class="t-mark-rev t-since-cxx11">(C++11 起)</span></span></span></div>
|
|
<div class="t-li1"><span class="t-li">5)</span> 返回 <code>searcher.operator()</code> 的结果，即指向找到的子串位置的迭代器，或若找不到则为 <code>last</code> 。</div>
|
|
<h3><span class="mw-headline" id=".E5.A4.8D.E6.9D.82.E5.BA.A6">复杂度</span></h3>
|
|
<div class="t-li1"><span class="t-li">1-4)</span> 至多 <code>S*N</code> 次搜索，其中 <span class="t-c"><span class="mw-geshi cpp source-cpp">S <span class="sy1">=</span> <a href="cpp-iterator-distance.html"><span class="kw673">std::<span class="me2">distance</span></span></a><span class="br0">(</span>s_first, s_last<span class="br0">)</span></span></span> 而 <span class="t-c"><span class="mw-geshi cpp source-cpp">N <span class="sy1">=</span> <a href="cpp-iterator-distance.html"><span class="kw673">std::<span class="me2">distance</span></span></a><span class="br0">(</span>first, last<span class="br0">)</span></span></span> 。</div>
|
|
<div class="t-li1"><span class="t-li">5)</span> 依赖于搜索器</div>
|
|
<h3><span class="mw-headline" id=".E5.BC.82.E5.B8.B8">异常</span></h3>
|
|
<p>拥有名为 <code>ExecutionPolicy</code> 的模板形参的重载按下列方式报告错误：</p>
|
|
<ul>
|
|
<li>若作为算法一部分调用的函数的执行抛出异常，且 <code>ExecutionPolicy</code> 为<a href="cpp-algorithm-execution_policy_tag_t.html">标准策略</a>之一，则调用 <span class="t-lc"><a href="cpp-error-terminate.html">std::terminate</a></span> 。对于任何其他 <code>ExecutionPolicy</code> ，行为是实现定义的。</li>
|
|
<li>若算法无法分配内存，则抛出 <span class="t-lc"><a href="cpp-memory-new-bad_alloc.html">std::bad_alloc</a></span> 。</li>
|
|
</ul>
|
|
<h3><span class="mw-headline" id=".E5.8F.AF.E8.83.BD.E7.9A.84.E5.AE.9E.E7.8E.B0">可能的实现</span></h3>
|
|
<table class="eq-fun-cpp-table">
|
|
<tr>
|
|
<th>版本一</th>
|
|
</tr>
|
|
<tr>
|
|
<td>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2<span class="sy1">></span>
|
|
ForwardIt1 search<span class="br0">(</span>ForwardIt1 first, ForwardIt1 last,
|
|
ForwardIt2 s_first, ForwardIt2 s_last<span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span><span class="sy4">;</span> <span class="sy4">;</span> <span class="sy2">++</span>first<span class="br0">)</span> <span class="br0">{</span>
|
|
ForwardIt1 it <span class="sy1">=</span> first<span class="sy4">;</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span>ForwardIt2 s_it <span class="sy1">=</span> s_first<span class="sy4">;</span> <span class="sy4">;</span> <span class="sy2">++</span>it, <span class="sy2">++</span>s_it<span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">if</span> <span class="br0">(</span>s_it <span class="sy1">==</span> s_last<span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">return</span> first<span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<span class="kw1">if</span> <span class="br0">(</span>it <span class="sy1">==</span> last<span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">return</span> last<span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<span class="kw1">if</span> <span class="br0">(</span><span class="sy3">!</span><span class="br0">(</span><span class="sy2">*</span>it <span class="sy1">==</span> <span class="sy2">*</span>s_it<span class="br0">)</span><span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">break</span><span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<span class="br0">}</span>
|
|
<span class="br0">}</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
</td>
|
|
</tr>
|
|
<tr>
|
|
<th>版本二</th>
|
|
</tr>
|
|
<tr>
|
|
<td>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="kw1">template</span><span class="sy1"><</span><span class="kw1">class</span> ForwardIt1, <span class="kw1">class</span> ForwardIt2, <span class="kw1">class</span> BinaryPredicate<span class="sy1">></span>
|
|
ForwardIt1 search<span class="br0">(</span>ForwardIt1 first, ForwardIt1 last,
|
|
ForwardIt2 s_first, ForwardIt2 s_last,
|
|
BinaryPredicate p<span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span><span class="sy4">;</span> <span class="sy4">;</span> <span class="sy2">++</span>first<span class="br0">)</span> <span class="br0">{</span>
|
|
ForwardIt1 it <span class="sy1">=</span> first<span class="sy4">;</span>
|
|
<span class="kw1">for</span> <span class="br0">(</span>ForwardIt2 s_it <span class="sy1">=</span> s_first<span class="sy4">;</span> <span class="sy4">;</span> <span class="sy2">++</span>it, <span class="sy2">++</span>s_it<span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">if</span> <span class="br0">(</span>s_it <span class="sy1">==</span> s_last<span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">return</span> first<span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<span class="kw1">if</span> <span class="br0">(</span>it <span class="sy1">==</span> last<span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">return</span> last<span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<span class="kw1">if</span> <span class="br0">(</span><span class="sy3">!</span>p<span class="br0">(</span><span class="sy2">*</span>it, <span class="sy2">*</span>s_it<span class="br0">)</span><span class="br0">)</span> <span class="br0">{</span>
|
|
<span class="kw1">break</span><span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
<span class="br0">}</span>
|
|
<span class="br0">}</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
<h3><span class="mw-headline" id=".E7.A4.BA.E4.BE.8B">示例</span></h3>
|
|
<div class="t-example">
|
|
<div class="t-example-live-link"></div>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="cpp source-cpp">
|
|
<pre class="de1"><span class="co2">#include <string></span>
|
|
<span class="co2">#include <algorithm></span>
|
|
<span class="co2">#include <iostream></span>
|
|
<span class="co2">#include <vector></span>
|
|
<span class="co2">#include <functional></span>
|
|
|
|
<span class="kw1">template</span><span class="sy1"><</span><span class="kw1">typename</span> Container<span class="sy1">></span>
|
|
<span class="kw4">bool</span> in_quote<span class="br0">(</span><span class="kw4">const</span> Container<span class="sy3">&</span> cont, <span class="kw4">const</span> <a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a><span class="sy3">&</span> s<span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<span class="kw1">return</span> std<span class="sy4">::</span><span class="me2">search</span><span class="br0">(</span>cont.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, cont.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>, s.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, s.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span> <span class="sy3">!</span><span class="sy1">=</span> cont.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="br0">}</span>
|
|
|
|
<span class="kw4">int</span> main<span class="br0">(</span><span class="br0">)</span>
|
|
<span class="br0">{</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> str <span class="sy1">=</span> <span class="st0">"why waste time learning, when ignorance is instantaneous?"</span><span class="sy4">;</span>
|
|
<span class="co1">// str.find() 也能使用</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-boolalpha.html"><span class="kw1763">std::<span class="me2">boolalpha</span></span></a> <span class="sy1"><<</span> in_quote<span class="br0">(</span>str, <span class="st0">"learning"</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
|
|
<span class="sy1"><<</span> in_quote<span class="br0">(</span>str, <span class="st0">"lemming"</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
|
|
<a href="cpp-container-vector.html"><span class="kw1269">std::<span class="me2">vector</span></span></a><span class="sy1"><</span><span class="kw4">char</span><span class="sy1">></span> vec<span class="br0">(</span>str.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, str.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <a href="cpp-io-manip-boolalpha.html"><span class="kw1763">std::<span class="me2">boolalpha</span></span></a> <span class="sy1"><<</span> in_quote<span class="br0">(</span>vec, <span class="st0">"learning"</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span>
|
|
<span class="sy1"><<</span> in_quote<span class="br0">(</span>vec, <span class="st0">"lemming"</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
|
|
<span class="co1">// C++17 重载演示：</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> in <span class="sy1">=</span> <span class="st0">"Lorem ipsum dolor sit amet, consectetur adipiscing elit,"</span>
|
|
<span class="st0">" sed do eiusmod tempor incididunt ut labore et dolore magna aliqua"</span><span class="sy4">;</span>
|
|
<a href="cpp-string-basic_string.html"><span class="kw1230">std::<span class="me2">string</span></span></a> needle <span class="sy1">=</span> <span class="st0">"pisci"</span><span class="sy4">;</span>
|
|
<span class="kw4">auto</span> it <span class="sy1">=</span> std<span class="sy4">::</span><span class="me2">search</span><span class="br0">(</span>in.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, in.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span>,
|
|
<a href="cpp-utility-functional-boyer_moore_searcher.html"><span class="kw1063">std::<span class="me2">boyer_moore_searcher</span></span></a><span class="br0">(</span>
|
|
needle.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span>, needle.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span><span class="br0">)</span><span class="sy4">;</span>
|
|
<span class="kw1">if</span><span class="br0">(</span>it <span class="sy3">!</span><span class="sy1">=</span> in.<span class="me1">end</span><span class="br0">(</span><span class="br0">)</span><span class="br0">)</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"The string "</span> <span class="sy1"><<</span> needle <span class="sy1"><<</span> <span class="st0">" found at offset "</span>
|
|
<span class="sy1"><<</span> it <span class="sy2">-</span> in.<span class="me1">begin</span><span class="br0">(</span><span class="br0">)</span> <span class="sy1"><<</span> <span class="st0">'<span class="es1">\n</span>'</span><span class="sy4">;</span>
|
|
<span class="kw1">else</span>
|
|
<a href="cpp-io-cout.html"><span class="kw1757">std::<span class="me2">cout</span></span></a> <span class="sy1"><<</span> <span class="st0">"The string "</span> <span class="sy1"><<</span> needle <span class="sy1"><<</span> <span class="st0">" not found<span class="es1">\n</span>"</span><span class="sy4">;</span>
|
|
<span class="br0">}</span></pre></div>
|
|
</div>
|
|
<p>输出：</p>
|
|
<div dir="ltr" class="mw-geshi" style="text-align: left;">
|
|
<div class="text source-text">
|
|
<pre class="de1">true
|
|
false
|
|
true
|
|
false
|
|
The string pisci found at offset 43</pre></div>
|
|
</div>
|
|
</div>
|
|
<h3><span class="mw-headline" id=".E5.8F.82.E9.98.85">参阅</span></h3>
|
|
<table class="t-dsc-begin">
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-find_end.html"><span class="t-lines"><span>find_end</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>在特定范围中寻找最后出现的元素序列<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-includes.html"><span class="t-lines"><span>includes</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>若一个序列是另一个的子列则返回 true<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-equal.html"><span class="t-lines"><span>equal</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>确定两个元素集合是否是相同的<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-find.html"><span class="t-lines"><span>find</span><span>find_if</span><span>find_if_not</span></span></a></div>
|
|
<div><span class="t-lines"><span></span><span></span><span><span class="t-mark-rev t-since-cxx11">(C++11)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>寻找首个满足特定判别标准的元素<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-lexicographical_compare.html"><span class="t-lines"><span>lexicographical_compare</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>当一个范围按字典顺序小于另一个范围时，返回 true<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-mismatch.html"><span class="t-lines"><span>mismatch</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>寻找两个范围出现不同的首个位置<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-algorithm-search_n.html"><span class="t-lines"><span>search_n</span></span></a></div>
|
|
</div>
|
|
</td>
|
|
<td>在范围中搜索一定量的某个元素的连续副本<br />
|
|
<span class="t-mark">(函数模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-default_searcher.html"><span class="t-lines"><span>default_searcher</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>标准 C++ 库搜索算法实现<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-boyer_moore_searcher.html"><span class="t-lines"><span>boyer_moore_searcher</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>Boyer-Moore 搜索算法实现<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
<tr class="t-dsc">
|
|
<td>
|
|
<div class="t-dsc-member-div">
|
|
<div><a href="cpp-utility-functional-boyer_moore_horspool_searcher.html"><span class="t-lines"><span>boyer_moore_horspool_searcher</span></span></a></div>
|
|
<div><span class="t-lines"><span><span class="t-mark-rev t-since-cxx17">(C++17)</span></span></span></div>
|
|
</div>
|
|
</td>
|
|
<td>Boyer-Moore-Horspool 搜索算法实现<br />
|
|
<span class="t-mark">(类模板)</span></td>
|
|
</tr>
|
|
</table>
|
|
</div>
|
|
<div class="visualClear"></div>
|
|
</div>
|
|
</div>
|
|
</div>
|
|
</body>
|
|
</html>
|