backup/C-Plus-Plus
1
0
Fork 0
mirror of https://github.com/TheAlgorithms/C-Plus-Plus.git synced 2026-05-11 19:17:21 +08:00
Code Issues Projects Releases Wiki Activity

Documentation for f308a05a87

Browse Source
This commit is contained in:
github-actions
2020-08-23 11:29:37 +00:00
parent 00c8db1c8b
commit 505bb2bd90
153 changed files with 3304 additions and 3078 deletions
Download Patch File Download Diff File Expand all files Collapse all files

297
d9/d69/median__search_8cpp.html
View File

@@ -90,100 +90,54 @@ $(document).ready(function(){initNavTree('d9/d69/median__search_8cpp.html','../.
</div>
<div class="header">
<div class="summary">
<a href="#namespaces">Namespaces</a> &#124;
<a href="#func-members">Functions</a> </div>
<div class="headertitle">
<div class="title">median_search.cpp File Reference</div> </div>
</div><!--header-->
<div class="contents">
<p><a href="https://en.wikipedia.org/wiki/Median_search">Median search</a> algorithm
<p>Implementation of <a href="https://en.wikipedia.org/wiki/Median_of_medians">Median search</a> algorithm. @cases from <a href="https://brilliant.org/wiki/median-finding-algorithm/">here</a>
<a href="#details">More...</a></p>
<div class="textblock"><code>#include &lt;algorithm&gt;</code><br />
<code>#include &lt;iostream&gt;</code><br />
<div class="textblock"><code>#include &lt;iostream&gt;</code><br />
<code>#include &lt;algorithm&gt;</code><br />
<code>#include &lt;vector&gt;</code><br />
<code>#include &lt;cassert&gt;</code><br />
</div><div class="textblock"><div class="dynheader">
Include dependency graph for median_search.cpp:</div>
<div class="dyncontent">
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d2/d89/median__search_8cpp__incl.svg" width="264" height="112"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d2/d89/median__search_8cpp__incl.svg" width="355" height="112"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
</div>
</div>
</div><table class="memberdecls">
<tr class="memitem:a55bfdcfe7613d75fb48ec99c7bf4dd5e"><td class="memItemLeft" align="right" valign="top"><a id="a55bfdcfe7613d75fb48ec99c7bf4dd5e"></a>
#define&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d69/median__search_8cpp.html#a55bfdcfe7613d75fb48ec99c7bf4dd5e">MAX_NUM</a>&#160;&#160;&#160;20</td></tr>
<tr class="memdesc:a55bfdcfe7613d75fb48ec99c7bf4dd5e"><td class="mdescLeft">&#160;</td><td class="mdescRight">maximum number of values to sort from <br /></td></tr>
<tr class="separator:a55bfdcfe7613d75fb48ec99c7bf4dd5e"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:a3a66390d0e407dce4fcbf63a169c6c8f"><td class="memTemplParams" colspan="2">template&lt;class X &gt; </td></tr>
<tr class="memitem:a3a66390d0e407dce4fcbf63a169c6c8f"><td class="memTemplItemLeft" align="right" valign="top">void&#160;</td><td class="memTemplItemRight" valign="bottom"><a class="el" href="../../d9/d69/median__search_8cpp.html#a3a66390d0e407dce4fcbf63a169c6c8f">comp</a> (X x, <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; *s1, <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; *s2, <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; *s3)</td></tr>
<tr class="separator:a3a66390d0e407dce4fcbf63a169c6c8f"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="namespaces"></a>
Namespaces</h2></td></tr>
<tr class="memitem:d9/dca/namespacesearch"><td class="memItemLeft" align="right" valign="top"> &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/dca/namespacesearch.html">search</a></td></tr>
<tr class="memdesc:d9/dca/namespacesearch"><td class="mdescLeft">&#160;</td><td class="mdescRight">Search algorithms. <br /></td></tr>
<tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:da/dd4/namespacemedian__search"><td class="memItemLeft" align="right" valign="top"> &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../da/dd4/namespacemedian__search.html">median_search</a></td></tr>
<tr class="memdesc:da/dd4/namespacemedian__search"><td class="mdescLeft">&#160;</td><td class="mdescRight">Functions for <a href="https://en.wikipedia.org/wiki/Median_search">Median search</a> algorithm. <br /></td></tr>
<tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table><table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="func-members"></a>
Functions</h2></td></tr>
<tr class="memitem:a868847218f694e78bf433a0ff7648bae"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">search::median_search::median_of_medians</a> (const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; &amp;A, const int &amp;idx)</td></tr>
<tr class="separator:a868847218f694e78bf433a0ff7648bae"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ae1a3968e7947464bee7714f6d43b7002"><td class="memItemLeft" align="right" valign="top">void&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d69/median__search_8cpp.html#ae1a3968e7947464bee7714f6d43b7002">test</a> ()</td></tr>
<tr class="separator:ae1a3968e7947464bee7714f6d43b7002"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:ae66f6b31b5ad750f1fe042a706a4e3d4"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d9/d69/median__search_8cpp.html#ae66f6b31b5ad750f1fe042a706a4e3d4">main</a> ()</td></tr>
<tr class="separator:ae66f6b31b5ad750f1fe042a706a4e3d4"><td class="memSeparator" colspan="2">&#160;</td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p><a href="https://en.wikipedia.org/wiki/Median_search">Median search</a> algorithm </p>
<dl class="section warning"><dt>Warning</dt><dd>This core is erroneous and gives invorrect answers. Tested using cases from <a href="https://brilliant.org/wiki/median-finding-algorithm/">here</a> </dd></dl>
<div class="textblock"><p>Implementation of <a href="https://en.wikipedia.org/wiki/Median_of_medians">Median search</a> algorithm. @cases from <a href="https://brilliant.org/wiki/median-finding-algorithm/">here</a> </p>
<p>Given an array A[1,...,n] of n numbers and an index i, where 1 ≤ i ≤ n, find the i-th smallest element of A. median_of_medians(A, i): #divide A into sublists of len 5 sublists = [A[j:j+5] for j in range(0, len(A), 5)] medians = [sorted(sublist)[len(sublist)/2] for sublist in sublists] if len(medians) &lt;= 5: pivot = sorted(medians)[len(medians)/2] else: #the pivot is the median of the medians pivot = median_of_medians(medians, len(medians)/2) #partitioning step low = [j for j in A if j &lt; pivot] high = [j for j in A if j &gt; pivot] k = len(low) if i &lt; k: return median_of_medians(low,i) elif i &gt; k: return median_of_medians(high,i-k-1) else: #pivot = k return pivot</p>
<dl class="section note"><dt>Note</dt><dd>this algorithm implements median search for only arrays which have distinct elements</dd></dl>
<p>Here are some example lists you can use to see how the algorithm works A = [1,2,3,4,5,1000,8,9,99] (Contain Unique Elements) B = [1,2,3,4,5,6] (Contains Unique Elements) print median_of_medians(A, 0) #should be 1 print median_of_medians(A,7) #should be 99 print median_of_medians(B,4) #should be 5</p>
<dl class="section author"><dt>Author</dt><dd>Unknown author </dd>
<dd>
<a href="https://github.com/Rp-sushil">Sushil Kumar</a> </dd></dl>
</div><h2 class="groupheader">Function Documentation</h2>
<a id="a3a66390d0e407dce4fcbf63a169c6c8f"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a3a66390d0e407dce4fcbf63a169c6c8f">&#9670;&nbsp;</a></span>comp()</h2>
<div class="memitem">
<div class="memproto">
<div class="memtemplate">
template&lt;class X &gt; </div>
<table class="memname">
<tr>
<td class="memname">void comp </td>
<td>(</td>
<td class="paramtype">X&#160;</td>
<td class="paramname"><em>x</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; *&#160;</td>
<td class="paramname"><em>s1</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; *&#160;</td>
<td class="paramname"><em>s2</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; *&#160;</td>
<td class="paramname"><em>s3</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<dl class="todo"><dt><b><a class="el" href="../../dd/da0/todo.html#_todo000013">Todo:</a></b></dt><dd>add documentation </dd></dl>
<div class="fragment"><div class="line"><a name="l00018"></a><span class="lineno"> 18</span>&#160; {</div>
<div class="line"><a name="l00019"></a><span class="lineno"> 19</span>&#160; <span class="keywordflow">if</span> (s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() &gt;= x &amp;&amp; s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() + s2-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() &lt; x) {</div>
<div class="line"><a name="l00020"></a><span class="lineno"> 20</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; (*s2)[0] &lt;&lt; <span class="stringliteral">&quot; is the &quot;</span> &lt;&lt; x + 1 &lt;&lt; <span class="stringliteral">&quot;th element from front&quot;</span>;</div>
<div class="line"><a name="l00021"></a><span class="lineno"> 21</span>&#160; } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() &gt; x) {</div>
<div class="line"><a name="l00022"></a><span class="lineno"> 22</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/sort.html">std::sort</a>(s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/begin.html">begin</a>(), s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/end.html">end</a>());</div>
<div class="line"><a name="l00023"></a><span class="lineno"> 23</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; (*s1)[x] &lt;&lt; <span class="stringliteral">&quot; is the &quot;</span> &lt;&lt; x + 1 &lt;&lt; <span class="stringliteral">&quot;th element from front&quot;</span>;</div>
<div class="line"><a name="l00024"></a><span class="lineno"> 24</span>&#160; } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() + s2-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() &lt;= x &amp;&amp; s3-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() &gt; x) {</div>
<div class="line"><a name="l00025"></a><span class="lineno"> 25</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/sort.html">std::sort</a>(s3-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/begin.html">begin</a>(), s3-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/end.html">end</a>());</div>
<div class="line"><a name="l00026"></a><span class="lineno"> 26</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; (*s3)[x - s1-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>() - s2-&gt;<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>()] &lt;&lt; <span class="stringliteral">&quot; is the &quot;</span> &lt;&lt; x + 1</div>
<div class="line"><a name="l00027"></a><span class="lineno"> 27</span>&#160; &lt;&lt; <span class="stringliteral">&quot;th element from front&quot;</span>;</div>
<div class="line"><a name="l00028"></a><span class="lineno"> 28</span>&#160; } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00029"></a><span class="lineno"> 29</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; x + 1 &lt;&lt; <span class="stringliteral">&quot; is invalid location&quot;</span>;</div>
<div class="line"><a name="l00030"></a><span class="lineno"> 30</span>&#160; }</div>
<div class="line"><a name="l00031"></a><span class="lineno"> 31</span>&#160;}</div>
</div><!-- fragment --><div class="dynheader">
Here is the call graph for this function:</div>
<div class="dyncontent">
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d9/d69/median__search_8cpp_a3a66390d0e407dce4fcbf63a169c6c8f_cgraph.svg" width="236" height="190"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
</div>
</div>
</div>
</div>
<a id="ae66f6b31b5ad750f1fe042a706a4e3d4"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ae66f6b31b5ad750f1fe042a706a4e3d4">&#9670;&nbsp;</a></span>main()</h2>
@@ -199,53 +153,156 @@ Here is the call graph for this function:</div>
</table>
</div><div class="memdoc">
<p>Main function </p>
<div class="fragment"><div class="line"><a name="l00038"></a><span class="lineno"> 38</span>&#160; {</div>
<div class="line"><a name="l00039"></a><span class="lineno"> 39</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> v{25, 21, 98, 100, 76, 22, 43, 60, 89, 87};</div>
<div class="line"><a name="l00040"></a><span class="lineno"> 40</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> s1;</div>
<div class="line"><a name="l00041"></a><span class="lineno"> 41</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> s2;</div>
<div class="line"><a name="l00042"></a><span class="lineno"> 42</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> s3;</div>
<div class="line"><a name="l00043"></a><span class="lineno"> 43</span>&#160; </div>
<div class="line"><a name="l00044"></a><span class="lineno"> 44</span>&#160; <span class="comment">// creates an array of random numbers</span></div>
<div class="line"><a name="l00045"></a><span class="lineno"> 45</span>&#160; <span class="comment">// for (int i = 0; i &lt; MAX_NUM; i++) {</span></div>
<div class="line"><a name="l00046"></a><span class="lineno"> 46</span>&#160; <span class="comment">// int r = std::rand() % 1000;</span></div>
<div class="line"><a name="l00047"></a><span class="lineno"> 47</span>&#160; <span class="comment">// v.push_back(r);</span></div>
<div class="line"><a name="l00048"></a><span class="lineno"> 48</span>&#160; <span class="comment">// std::cout &lt;&lt; r &lt;&lt; &quot; &quot;;</span></div>
<div class="line"><a name="l00049"></a><span class="lineno"> 49</span>&#160; <span class="comment">// }</span></div>
<div class="line"><a name="l00050"></a><span class="lineno"> 50</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> r : v) <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; r &lt;&lt; <span class="stringliteral">&quot; &quot;</span>;</div>
<div class="line"><a name="l00051"></a><span class="lineno"> 51</span>&#160; </div>
<div class="line"><a name="l00052"></a><span class="lineno"> 52</span>&#160; <span class="keywordtype">int</span> median = <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/numeric/random/rand.html">std::rand</a>() % 1000; <span class="comment">// initialize to a random numnber</span></div>
<div class="line"><a name="l00053"></a><span class="lineno"> 53</span>&#160; </div>
<div class="line"><a name="l00054"></a><span class="lineno"> 54</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;\nmedian=&quot;</span> &lt;&lt; median &lt;&lt; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/manip/endl.html">std::endl</a>;</div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span>&#160; <span class="keywordtype">int</span> avg1, avg2, avg3, sum1 = 0, sum2 = 0, sum3 = 0;</div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span>&#160; </div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span>&#160; <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; v.size(); i++) { <span class="comment">// iterate through all numbers</span></div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>&#160; <span class="keywordflow">if</span> (v.back() == v[median]) {</div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>&#160; avg1 = sum1 + v.back();</div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>&#160; s2.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">push_back</a>(v.back());</div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>&#160; } <span class="keywordflow">else</span> <span class="keywordflow">if</span> (v.back() &lt; v[median]) {</div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>&#160; avg2 = sum2 + v.back();</div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>&#160; s1.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">push_back</a>(v.back());</div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>&#160; } <span class="keywordflow">else</span> {</div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>&#160; avg3 = sum3 + v.back();</div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>&#160; s3.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">push_back</a>(v.back());</div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>&#160; }</div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>&#160; v.pop_back();</div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>&#160; }</div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span>&#160; </div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span>&#160; <span class="keywordtype">int</span> x;</div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;enter the no. to be searched form begining:- &quot;</span>;</div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_istream.html">std::cin</a> &gt;&gt; x;</div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span>&#160; <a class="code" href="../../d9/d69/median__search_8cpp.html#a3a66390d0e407dce4fcbf63a169c6c8f">comp</a>(x - 1, &amp;s1, &amp;s2, &amp;s3);</div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span>&#160; </div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span>&#160; <span class="keywordflow">return</span> 0;</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>&#160;}</div>
<div class="fragment"><div class="line"><a name="l00129"></a><span class="lineno"> 129</span>&#160;{</div>
<div class="line"><a name="l00130"></a><span class="lineno"> 130</span>&#160; <a class="code" href="../../d9/d69/median__search_8cpp.html#ae1a3968e7947464bee7714f6d43b7002">test</a>();</div>
<div class="line"><a name="l00131"></a><span class="lineno"> 131</span>&#160; <span class="keywordtype">int</span> n = 0;</div>
<div class="line"><a name="l00132"></a><span class="lineno"> 132</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Enter Size of Array: &quot;</span>;</div>
<div class="line"><a name="l00133"></a><span class="lineno"> 133</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_istream.html">std::cin</a> &gt;&gt; n;</div>
<div class="line"><a name="l00134"></a><span class="lineno"> 134</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> a(n);</div>
<div class="line"><a name="l00135"></a><span class="lineno"> 135</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Enter Array: &quot;</span>;</div>
<div class="line"><a name="l00136"></a><span class="lineno"> 136</span>&#160; <span class="keywordflow">for</span>(<span class="keywordtype">int</span> i = 0; i &lt; n; i++){</div>
<div class="line"><a name="l00137"></a><span class="lineno"> 137</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_istream.html">std::cin</a> &gt;&gt; a[i];</div>
<div class="line"><a name="l00138"></a><span class="lineno"> 138</span>&#160; }</div>
<div class="line"><a name="l00139"></a><span class="lineno"> 139</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Median: &quot;</span>; <span class="comment">// Median defination: https://en.wikipedia.org/wiki/Median</span></div>
<div class="line"><a name="l00140"></a><span class="lineno"> 140</span>&#160; <span class="keywordtype">int</span> x = <a class="code" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">search::median_search::median_of_medians</a>(a, (n - 1) / 2);</div>
<div class="line"><a name="l00141"></a><span class="lineno"> 141</span>&#160; <span class="keywordflow">if</span>(n % 2 == 0){</div>
<div class="line"><a name="l00142"></a><span class="lineno"> 142</span>&#160; <span class="keywordtype">int</span> y = <a class="code" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">search::median_search::median_of_medians</a>(a, n / 2);</div>
<div class="line"><a name="l00143"></a><span class="lineno"> 143</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; (float(x) + float(y))/2.0;</div>
<div class="line"><a name="l00144"></a><span class="lineno"> 144</span>&#160; }</div>
<div class="line"><a name="l00145"></a><span class="lineno"> 145</span>&#160; <span class="keywordflow">else</span>{</div>
<div class="line"><a name="l00146"></a><span class="lineno"> 146</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; x;</div>
<div class="line"><a name="l00147"></a><span class="lineno"> 147</span>&#160; }</div>
<div class="line"><a name="l00148"></a><span class="lineno"> 148</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;\nTo find i-th smallest element &quot;</span>;</div>
<div class="line"><a name="l00149"></a><span class="lineno"> 149</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;\nEnter i: &quot;</span>;</div>
<div class="line"><a name="l00150"></a><span class="lineno"> 150</span>&#160; <span class="keywordtype">int</span> idx = 0;</div>
<div class="line"><a name="l00151"></a><span class="lineno"> 151</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_istream.html">std::cin</a> &gt;&gt; idx;</div>
<div class="line"><a name="l00152"></a><span class="lineno"> 152</span>&#160; idx--;</div>
<div class="line"><a name="l00153"></a><span class="lineno"> 153</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; idx + 1&lt;&lt; <span class="stringliteral">&quot;-th smallest element: &quot;</span> &lt;&lt; <a class="code" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">search::median_search::median_of_medians</a>(a, idx) &lt;&lt; <span class="charliteral">&#39;\n&#39;</span>;</div>
<div class="line"><a name="l00154"></a><span class="lineno"> 154</span>&#160; <span class="keywordflow">return</span> 0;</div>
<div class="line"><a name="l00155"></a><span class="lineno"> 155</span>&#160;}</div>
</div><!-- fragment --><div class="dynheader">
Here is the call graph for this function:</div>
<div class="dyncontent">
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d9/d69/median__search_8cpp_ae66f6b31b5ad750f1fe042a706a4e3d4_cgraph.svg" width="435" height="266"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d9/d69/median__search_8cpp_ae66f6b31b5ad750f1fe042a706a4e3d4_cgraph.svg" width="154" height="38"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
</div>
</div>
</div>
</div>
<a id="a868847218f694e78bf433a0ff7648bae"></a>
<h2 class="memtitle"><span class="permalink"><a href="#a868847218f694e78bf433a0ff7648bae">&#9670;&nbsp;</a></span>median_of_medians()</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">int search::median_search::median_of_medians </td>
<td>(</td>
<td class="paramtype">const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector</a>&lt; int &gt; &amp;&#160;</td>
<td class="paramname"><em>A</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">const int &amp;&#160;</td>
<td class="paramname"><em>idx</em>&#160;</td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td></td>
</tr>
</table>
</div><div class="memdoc">
<p>This function search the element in an array for the given index. </p><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">A</td><td>array where numbers are saved </td></tr>
<tr><td class="paramname">idx</td><td>current index in array </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>corresponding element which we want to search. </dd></dl>
<div class="fragment"><div class="line"><a name="l00062"></a><span class="lineno"> 62</span>&#160; {</div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>&#160; <span class="keywordtype">int</span> pivot = 0; <span class="comment">// initialized with zero</span></div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> a(A.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/begin.html">begin</a>(), A.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/end.html">end</a>());</div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> m;</div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>&#160; <span class="keywordtype">int</span> r = a.size();</div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>&#160; <span class="keywordflow">for</span>(<span class="keywordtype">int</span> i = 0; i &lt; r; i += 5){</div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/sort.html">std::sort</a>(a.begin() + i, a.begin() + <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/min.html">std::min</a>(r, i + 5));</div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>&#160; <span class="keywordtype">int</span> mid = (i + <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/min.html">std::min</a>(r, i + 5)) / 2;</div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span>&#160; m.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">push_back</a>(a[mid]);</div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span>&#160; }</div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span>&#160; <span class="keywordtype">int</span> sz = int(m.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>());</div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span>&#160; <span class="keywordflow">if</span>(sz &lt;= 5){</div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/sort.html">std::sort</a>(m.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/begin.html">begin</a>(), m.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/end.html">end</a>());</div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span>&#160; pivot = m[(sz- 1) / 2];</div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span>&#160; }</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>&#160; <span class="keywordflow">else</span>{</div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>&#160; pivot = <a class="code" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">median_of_medians</a>(m, idx);</div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span>&#160; }</div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> low;</div>
<div class="line"><a name="l00081"></a><span class="lineno"> 81</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> high;</div>
<div class="line"><a name="l00082"></a><span class="lineno"> 82</span>&#160; <span class="keywordflow">for</span>(<span class="keywordtype">int</span> i = 0; i &lt; r; i++){</div>
<div class="line"><a name="l00083"></a><span class="lineno"> 83</span>&#160; <span class="keywordflow">if</span>(a[i] &lt; pivot){</div>
<div class="line"><a name="l00084"></a><span class="lineno"> 84</span>&#160; low.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">push_back</a>(a[i]);</div>
<div class="line"><a name="l00085"></a><span class="lineno"> 85</span>&#160; }</div>
<div class="line"><a name="l00086"></a><span class="lineno"> 86</span>&#160; <span class="keywordflow">else</span> <span class="keywordflow">if</span>(a[i] &gt; pivot){</div>
<div class="line"><a name="l00087"></a><span class="lineno"> 87</span>&#160; high.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">push_back</a>(a[i]);</div>
<div class="line"><a name="l00088"></a><span class="lineno"> 88</span>&#160; }</div>
<div class="line"><a name="l00089"></a><span class="lineno"> 89</span>&#160; }</div>
<div class="line"><a name="l00090"></a><span class="lineno"> 90</span>&#160; <span class="keywordtype">int</span> k = int(low.<a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector/size.html">size</a>());</div>
<div class="line"><a name="l00091"></a><span class="lineno"> 91</span>&#160; <span class="keywordflow">if</span>(idx &lt; k){</div>
<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>&#160; <span class="keywordflow">return</span> <a class="code" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">median_of_medians</a>(low, idx);</div>
<div class="line"><a name="l00093"></a><span class="lineno"> 93</span>&#160; }</div>
<div class="line"><a name="l00094"></a><span class="lineno"> 94</span>&#160; <span class="keywordflow">else</span> <span class="keywordflow">if</span>(idx &gt; k){</div>
<div class="line"><a name="l00095"></a><span class="lineno"> 95</span>&#160; <span class="keywordflow">return</span> <a class="code" href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">median_of_medians</a>(high, idx-k-1);</div>
<div class="line"><a name="l00096"></a><span class="lineno"> 96</span>&#160; }</div>
<div class="line"><a name="l00097"></a><span class="lineno"> 97</span>&#160; <span class="keywordflow">else</span>{</div>
<div class="line"><a name="l00098"></a><span class="lineno"> 98</span>&#160; <span class="keywordflow">return</span> pivot;</div>
<div class="line"><a name="l00099"></a><span class="lineno"> 99</span>&#160; }</div>
<div class="line"><a name="l00100"></a><span class="lineno"> 100</span>&#160;}</div>
</div><!-- fragment --><div class="dynheader">
Here is the call graph for this function:</div>
<div class="dyncontent">
<div class="center"><iframe scrolling="no" frameborder="0" src="../../d9/d69/median__search_8cpp_a868847218f694e78bf433a0ff7648bae_cgraph.svg" width="371" height="291"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe>
</div>
</div>
</div>
</div>
<a id="ae1a3968e7947464bee7714f6d43b7002"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ae1a3968e7947464bee7714f6d43b7002">&#9670;&nbsp;</a></span>test()</h2>
<div class="memitem">
<div class="memproto">
<table class="memname">
<tr>
<td class="memname">void test </td>
<td>(</td>
<td class="paramname"></td><td>)</td>
<td></td>
</tr>
</table>
</div><div class="memdoc">
<p>Function to test above algorithm </p>
<div class="fragment"><div class="line"><a name="l00107"></a><span class="lineno"> 107</span>&#160; {</div>
<div class="line"><a name="l00108"></a><span class="lineno"> 108</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> A{25,21,98,100,76,22,43,60,89,87};</div>
<div class="line"><a name="l00109"></a><span class="lineno"> 109</span>&#160; <span class="keywordtype">int</span> i = 3;</div>
<div class="line"><a name="l00110"></a><span class="lineno"> 110</span>&#160; assert(A[6] == search::median_search::median_of_medians(A, i)); <span class="comment">// A[6] = 43, is the fourth smallest element.</span></div>
<div class="line"><a name="l00111"></a><span class="lineno"> 111</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;test case:1 passed\n&quot;</span>;</div>
<div class="line"><a name="l00112"></a><span class="lineno"> 112</span>&#160; </div>
<div class="line"><a name="l00113"></a><span class="lineno"> 113</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> B{1,2,3,4,5,6};</div>
<div class="line"><a name="l00114"></a><span class="lineno"> 114</span>&#160; <span class="keywordtype">int</span> j = 4;</div>
<div class="line"><a name="l00115"></a><span class="lineno"> 115</span>&#160; assert(B[4] == search::median_search::median_of_medians(B, j)); <span class="comment">// B[4] = 5, is the fifth smallest element.</span></div>
<div class="line"><a name="l00116"></a><span class="lineno"> 116</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;test case:2 passed\n&quot;</span>;</div>
<div class="line"><a name="l00117"></a><span class="lineno"> 117</span>&#160; </div>
<div class="line"><a name="l00118"></a><span class="lineno"> 118</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/vector.html">std::vector&lt;int&gt;</a> C{1,2,3,4,5,1000,8,9,99};</div>
<div class="line"><a name="l00119"></a><span class="lineno"> 119</span>&#160; <span class="keywordtype">int</span> k = 3;</div>
<div class="line"><a name="l00120"></a><span class="lineno"> 120</span>&#160; assert(C[3] == search::median_search::median_of_medians(C, k)); <span class="comment">// C[3] = 4, is the fourth smallest element.</span></div>
<div class="line"><a name="l00121"></a><span class="lineno"> 121</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;test case:3 passed\n&quot;</span>;</div>
<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>&#160; <a class="codeRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;--All tests passed--\n&quot;</span>;</div>
<div class="line"><a name="l00123"></a><span class="lineno"> 123</span>&#160;}</div>
</div><!-- fragment -->
</div>
</div>
</div><!-- contents -->
@@ -255,10 +312,10 @@ Here is the call graph for this function:</div>
<div class="ttc" id="asort_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/algorithm/sort.html">std::sort</a></div><div class="ttdeci">T sort(T... args)</div></div>
<div class="ttc" id="apush_back_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/container/vector/push_back.html">std::vector::push_back</a></div><div class="ttdeci">T push_back(T... args)</div></div>
<div class="ttc" id="abasic_ostream_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a></div></div>
<div class="ttc" id="amedian__search_8cpp_html_a3a66390d0e407dce4fcbf63a169c6c8f"><div class="ttname"><a href="../../d9/d69/median__search_8cpp.html#a3a66390d0e407dce4fcbf63a169c6c8f">comp</a></div><div class="ttdeci">void comp(X x, std::vector&lt; int &gt; *s1, std::vector&lt; int &gt; *s2, std::vector&lt; int &gt; *s3)</div><div class="ttdef"><b>Definition:</b> median_search.cpp:17</div></div>
<div class="ttc" id="arand_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/numeric/random/rand.html">std::rand</a></div><div class="ttdeci">T rand(T... args)</div></div>
<div class="ttc" id="aendl_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/io/manip/endl.html">std::endl</a></div><div class="ttdeci">T endl(T... args)</div></div>
<div class="ttc" id="amedian__search_8cpp_html_a868847218f694e78bf433a0ff7648bae"><div class="ttname"><a href="../../d9/d69/median__search_8cpp.html#a868847218f694e78bf433a0ff7648bae">search::median_search::median_of_medians</a></div><div class="ttdeci">int median_of_medians(const std::vector&lt; int &gt; &amp;A, const int &amp;idx)</div><div class="ttdef"><b>Definition:</b> median_search.cpp:62</div></div>
<div class="ttc" id="amin_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/algorithm/min.html">std::min</a></div><div class="ttdeci">T min(T... args)</div></div>
<div class="ttc" id="abegin_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/container/vector/begin.html">std::vector::begin</a></div><div class="ttdeci">T begin(T... args)</div></div>
<div class="ttc" id="amedian__search_8cpp_html_ae1a3968e7947464bee7714f6d43b7002"><div class="ttname"><a href="../../d9/d69/median__search_8cpp.html#ae1a3968e7947464bee7714f6d43b7002">test</a></div><div class="ttdeci">void test()</div><div class="ttdef"><b>Definition:</b> median_search.cpp:107</div></div>
<div class="ttc" id="aend_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/container/vector/end.html">std::vector::end</a></div><div class="ttdeci">T end(T... args)</div></div>
<div class="ttc" id="abasic_istream_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/io/basic_istream.html">std::cin</a></div></div>
<!-- start footer part -->