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<p>The <a href="https://en.wikipedia.org/wiki/Knuth–Morris–Pratt_algorithm" target="_blank">Knuth-Morris-Pratt Algorithm</a> for finding a pattern within a piece of text with complexity O(n + m)
<a href="#details">More...</a></p>
<div class="textblock"><code>#include &lt;cassert&gt;</code><br />
<code>#include &lt;iostream&gt;</code><br />
<code>#include &lt;string&gt;</code><br />
<code>#include &lt;vector&gt;</code><br />
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Include dependency graph for knuth_morris_pratt.cpp:</div>
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<p><a href="../../de/d6a/knuth__morris__pratt_8cpp_source.html">Go to the source code of this file.</a></p>
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Namespaces</h2></td></tr>
<tr class="memitem:string_5Fsearch" id="r_string_5Fsearch"><td class="memItemLeft" align="right" valign="top">namespace &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d03/namespacestring__search.html">string_search</a></td></tr>
<tr class="memdesc:d9/d03/namespacestring__search"><td class="mdescLeft">&#160;</td><td class="mdescRight">String search algorithms. <br /></td></tr>
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Functions</h2></td></tr>
<tr class="memitem:a83c72ff237cdf623e42d4295e0029bf9" id="r_a83c72ff237cdf623e42d4295e0029bf9"><td class="memItemLeft" align="right" valign="top">std::vector&lt; size_t &gt;&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d03/namespacestring__search.html#a83c72ff237cdf623e42d4295e0029bf9">string_search::getFailureArray</a> (const std::string &amp;pattern)</td></tr>
<tr class="memdesc:a83c72ff237cdf623e42d4295e0029bf9"><td class="mdescLeft">&#160;</td><td class="mdescRight">Generate the partial match table aka failure function for a pattern to search. <br /></td></tr>
<tr class="memitem:a1e37af2f023495129cb57338c801209e" id="r_a1e37af2f023495129cb57338c801209e"><td class="memItemLeft" align="right" valign="top">size_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d03/namespacestring__search.html#a1e37af2f023495129cb57338c801209e">string_search::kmp</a> (const std::string &amp;pattern, const std::string &amp;text)</td></tr>
<tr class="memdesc:a1e37af2f023495129cb57338c801209e"><td class="mdescLeft">&#160;</td><td class="mdescRight">KMP algorithm to find a pattern in a text. <br /></td></tr>
<tr class="memitem:a483bb8ccf42aaf7375a83e91490eda1e" id="r_a483bb8ccf42aaf7375a83e91490eda1e"><td class="memItemLeft" align="right" valign="top">static void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="#a483bb8ccf42aaf7375a83e91490eda1e">tests</a> ()</td></tr>
<tr class="memdesc:a483bb8ccf42aaf7375a83e91490eda1e"><td class="mdescLeft">&#160;</td><td class="mdescRight">self-test implementations <br /></td></tr>
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<tr class="memitem:a1e37af2f023495129cb57338c801209e" id="r_a1e37af2f023495129cb57338c801209e"><td class="memItemLeft" align="right" valign="top">size_t&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="#a1e37af2f023495129cb57338c801209e">kmp</a> (const std::string &amp;pattern, const std::string &amp;text)</td></tr>
<tr class="memdesc:a1e37af2f023495129cb57338c801209e"><td class="mdescLeft">&#160;</td><td class="mdescRight">KMP algorithm to find a pattern in a text. <br /></td></tr>
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<a name="details" id="details"></a><h2 id="header-details" class="groupheader">Detailed Description</h2>
<div class="textblock"><p>The <a href="https://en.wikipedia.org/wiki/Knuth–Morris–Pratt_algorithm" target="_blank">Knuth-Morris-Pratt Algorithm</a> for finding a pattern within a piece of text with complexity O(n + m) </p>
<ol type="1">
<li>Preprocess pattern to identify any suffixes that are identical to prefixes. This tells us where to continue from if we get a mismatch between a character in our pattern and the text.</li>
<li>Step through the text one character at a time and compare it to a character in the pattern updating our location within the pattern if necessary <dl class="section author"><dt>Author</dt><dd><a href="https://github.com/Yancey2023" target="_blank">Yancey</a> </dd></dl>
</li>
</ol>
<p class="definition">Definition in file <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html">knuth_morris_pratt.cpp</a>.</p>
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<a id="a1e37af2f023495129cb57338c801209e" name="a1e37af2f023495129cb57338c801209e"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a1e37af2f023495129cb57338c801209e">&#9670;&#160;</a></span>kmp()</h2>
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<td class="memname">size_t string_search::kmp </td>
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<td class="paramtype">const std::string &amp;</td> <td class="paramname"><span class="paramname"><em>pattern</em></span>, </td>
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<p>KMP algorithm to find a pattern in a text. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">pattern</td><td>string pattern to search </td></tr>
<tr><td class="paramname">text</td><td>text in which to search </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>the starting index of the pattern if found </dd>
<dd>
<span class="tt">std::string::npos</span> if not found </dd></dl>
<p class="definition">Definition at line <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html#l00053">53</a> of file <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html">knuth_morris_pratt.cpp</a>.</p>
<div class="fragment"><div class="line"><span class="lineno"> 53</span> {</div>
<div class="line"><span class="lineno"> 54</span> <span class="keywordflow">if</span> (pattern.empty()) {</div>
<div class="line"><span class="lineno"> 55</span> <span class="keywordflow">return</span> 0;</div>
<div class="line"><span class="lineno"> 56</span> }</div>
<div class="line"><span class="lineno"> 57</span> std::vector&lt;size_t&gt; failure = <a class="code hl_function" href="../../d9/d03/namespacestring__search.html#a83c72ff237cdf623e42d4295e0029bf9">getFailureArray</a>(pattern);</div>
<div class="line"><span class="lineno"> 58</span> <span class="keywordtype">size_t</span> text_length = text.size();</div>
<div class="line"><span class="lineno"> 59</span> <span class="keywordtype">size_t</span> pattern_length = pattern.size();</div>
<div class="line"><span class="lineno"> 60</span> <span class="keywordtype">size_t</span> <a class="code hl_function" href="../../d4/d18/composite__simpson__rule_8cpp.html#a1b74d828b33760094906797042b89442">k</a> = 0;</div>
<div class="line"><span class="lineno"> 61</span> <span class="keywordflow">for</span> (<span class="keywordtype">size_t</span> j = 0; j &lt; text_length; j++) {</div>
<div class="line"><span class="lineno"> 62</span> <span class="keywordflow">while</span> (k != std::string::npos &amp;&amp; pattern[k] != text[j]) {</div>
<div class="line"><span class="lineno"> 63</span> <a class="code hl_function" href="../../d4/d18/composite__simpson__rule_8cpp.html#a1b74d828b33760094906797042b89442">k</a> = failure[<a class="code hl_function" href="../../d4/d18/composite__simpson__rule_8cpp.html#a1b74d828b33760094906797042b89442">k</a>];</div>
<div class="line"><span class="lineno"> 64</span> }</div>
<div class="line"><span class="lineno"> 65</span> <span class="keywordflow">if</span> (++k == pattern_length) {</div>
<div class="line"><span class="lineno"> 66</span> <span class="keywordflow">return</span> j - <a class="code hl_function" href="../../d4/d18/composite__simpson__rule_8cpp.html#a1b74d828b33760094906797042b89442">k</a> + 1;</div>
<div class="line"><span class="lineno"> 67</span> }</div>
<div class="line"><span class="lineno"> 68</span> }</div>
<div class="line"><span class="lineno"> 69</span> <span class="keywordflow">return</span> std::string::npos;</div>
<div class="line"><span class="lineno"> 70</span>}</div>
<div class="ttc" id="acomposite__simpson__rule_8cpp_html_a1b74d828b33760094906797042b89442"><div class="ttname"><a href="../../d4/d18/composite__simpson__rule_8cpp.html#a1b74d828b33760094906797042b89442">numerical_methods::simpson_method::k</a></div><div class="ttdeci">double k(double x)</div><div class="ttdoc">Another test function.</div><div class="ttdef"><b>Definition</b> <a href="../../d4/d18/composite__simpson__rule_8cpp_source.html#l00117">composite_simpson_rule.cpp:117</a></div></div>
<div class="ttc" id="anamespacestring__search_html_a83c72ff237cdf623e42d4295e0029bf9"><div class="ttname"><a href="../../d9/d03/namespacestring__search.html#a83c72ff237cdf623e42d4295e0029bf9">string_search::getFailureArray</a></div><div class="ttdeci">std::vector&lt; size_t &gt; getFailureArray(const std::string &amp;pattern)</div><div class="ttdoc">Generate the partial match table aka failure function for a pattern to search.</div><div class="ttdef"><b>Definition</b> <a href="../../de/d6a/knuth__morris__pratt_8cpp_source.html#l00032">knuth_morris_pratt.cpp:32</a></div></div>
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<h2 class="memtitle"><span class="permalink"><a href="#ae66f6b31b5ad750f1fe042a706a4e3d4">&#9670;&#160;</a></span>main()</h2>
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<p class="definition">Definition at line <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html#l00095">95</a> of file <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html">knuth_morris_pratt.cpp</a>.</p>
<div class="fragment"><div class="line"><span class="lineno"> 95</span> {</div>
<div class="line"><span class="lineno"> 96</span> <a class="code hl_function" href="#a483bb8ccf42aaf7375a83e91490eda1e">tests</a>();</div>
<div class="line"><span class="lineno"> 97</span> <span class="keywordflow">return</span> 0;</div>
<div class="line"><span class="lineno"> 98</span>}</div>
<div class="ttc" id="aknuth__morris__pratt_8cpp_html_a483bb8ccf42aaf7375a83e91490eda1e"><div class="ttname"><a href="#a483bb8ccf42aaf7375a83e91490eda1e">tests</a></div><div class="ttdeci">static void tests()</div><div class="ttdoc">self-test implementations</div><div class="ttdef"><b>Definition</b> <a href="../../de/d6a/knuth__morris__pratt_8cpp_source.html#l00079">knuth_morris_pratt.cpp:79</a></div></div>
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<h2 class="memtitle"><span class="permalink"><a href="#a483bb8ccf42aaf7375a83e91490eda1e">&#9670;&#160;</a></span>tests()</h2>
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<td class="memname">void tests </td>
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<p>self-test implementations </p>
<dl class="section return"><dt>Returns</dt><dd>void </dd></dl>
<p class="definition">Definition at line <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html#l00079">79</a> of file <a class="el" href="../../de/d6a/knuth__morris__pratt_8cpp_source.html">knuth_morris_pratt.cpp</a>.</p>
<div class="fragment"><div class="line"><span class="lineno"> 79</span> {</div>
<div class="line"><span class="lineno"> 80</span> assert(<a class="code hl_function" href="#a1e37af2f023495129cb57338c801209e">kmp</a>(<span class="stringliteral">&quot;abc1abc12l&quot;</span>, <span class="stringliteral">&quot;alskfjaldsabc1abc1abc12k2&quot;</span>) == std::string::npos);</div>
<div class="line"><span class="lineno"> 81</span> assert(<a class="code hl_function" href="#a1e37af2f023495129cb57338c801209e">kmp</a>(<span class="stringliteral">&quot;bca&quot;</span>, <span class="stringliteral">&quot;abcabc&quot;</span>) == 1);</div>
<div class="line"><span class="lineno"> 82</span> assert(<a class="code hl_function" href="#a1e37af2f023495129cb57338c801209e">kmp</a>(<span class="stringliteral">&quot;World&quot;</span>, <span class="stringliteral">&quot;helloWorld&quot;</span>) == 5);</div>
<div class="line"><span class="lineno"> 83</span> assert(<a class="code hl_function" href="#a1e37af2f023495129cb57338c801209e">kmp</a>(<span class="stringliteral">&quot;c++&quot;</span>, <span class="stringliteral">&quot;his_is_c++&quot;</span>) == 7);</div>
<div class="line"><span class="lineno"> 84</span> assert(<a class="code hl_function" href="#a1e37af2f023495129cb57338c801209e">kmp</a>(<span class="stringliteral">&quot;happy&quot;</span>, <span class="stringliteral">&quot;happy_coding&quot;</span>) == 0);</div>
<div class="line"><span class="lineno"> 85</span> assert(<a class="code hl_function" href="#a1e37af2f023495129cb57338c801209e">kmp</a>(<span class="stringliteral">&quot;&quot;</span>, <span class="stringliteral">&quot;pattern is empty&quot;</span>) == 0);</div>
<div class="line"><span class="lineno"> 86</span> </div>
<div class="line"><span class="lineno"> 87</span> <span class="comment">// this lets the user know that the tests have passed</span></div>
<div class="line"><span class="lineno"> 88</span> std::cout &lt;&lt; <span class="stringliteral">&quot;All KMP algorithm tests have successfully passed!\n&quot;</span>;</div>
<div class="line"><span class="lineno"> 89</span>}</div>
<div class="ttc" id="aknuth__morris__pratt_8cpp_html_a1e37af2f023495129cb57338c801209e"><div class="ttname"><a href="#a1e37af2f023495129cb57338c801209e">kmp</a></div><div class="ttdeci">size_t kmp(const std::string &amp;pattern, const std::string &amp;text)</div><div class="ttdoc">KMP algorithm to find a pattern in a text.</div><div class="ttdef"><b>Definition</b> <a href="../../de/d6a/knuth__morris__pratt_8cpp_source.html#l00053">knuth_morris_pratt.cpp:53</a></div></div>
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