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<p>Implementation of <a href="https://en.wikipedia.org/wiki/Kadane%27s_algorithm" target="_blank">Kadane Algorithm</a>
<a href="#details">More...</a></p>
<div class="textblock"><code>#include &lt;array&gt;</code><br />
<code>#include &lt;climits&gt;</code><br />
<code>#include &lt;iostream&gt;</code><br />
</div><div class="textblock"><div class="dynheader">
Include dependency graph for kadane2.cpp:</div>
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Namespaces</h2></td></tr>
<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">namespace &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../dd/d24/namespacedynamic__programming.html">dynamic_programming</a></td></tr>
<tr class="memdesc:dd/d24/namespacedynamic__programming"><td class="mdescLeft">&#160;</td><td class="mdescRight">Dynamic Programming algorithms. <br /></td></tr>
<tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">namespace &#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="../../d6/d74/namespacekadane.html">kadane</a></td></tr>
<tr class="memdesc:d6/d74/namespacekadane"><td class="mdescLeft">&#160;</td><td class="mdescRight">Functions for <a href="https://en.wikipedia.org/wiki/Kadane%27s_algorithm" target="_blank">Kadane</a> algorithm. <br /></td></tr>
<tr class="separator:"><td class="memSeparator" colspan="2">&#160;</td></tr>
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Functions</h2></td></tr>
<tr class="memitem:af3029007a422a914a85c0b0122f1c7b4" id="r_af3029007a422a914a85c0b0122f1c7b4"><td class="memTemplParams" colspan="2">template&lt;size_t N&gt; </td></tr>
<tr class="memitem:af3029007a422a914a85c0b0122f1c7b4"><td class="memTemplItemLeft" align="right" valign="top">int&#160;</td><td class="memTemplItemRight" valign="bottom"><a class="el" href="#af3029007a422a914a85c0b0122f1c7b4">dynamic_programming::kadane::maxSubArray</a> (const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/array.html">std::array</a>&lt; int, N &gt; &amp;n)</td></tr>
<tr class="memdesc:af3029007a422a914a85c0b0122f1c7b4"><td class="mdescLeft">&#160;</td><td class="mdescRight">maxSubArray function is used to calculate the maximum sum subarray and returns the value of maximum sum which is stored in the variable max_sum <br /></td></tr>
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<tr class="memitem:ae66f6b31b5ad750f1fe042a706a4e3d4" id="r_ae66f6b31b5ad750f1fe042a706a4e3d4"><td class="memItemLeft" align="right" valign="top">int&#160;</td><td class="memItemRight" valign="bottom"><a class="el" href="#ae66f6b31b5ad750f1fe042a706a4e3d4">main</a> ()</td></tr>
<tr class="memdesc:ae66f6b31b5ad750f1fe042a706a4e3d4"><td class="mdescLeft">&#160;</td><td class="mdescRight">Main function. <br /></td></tr>
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<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>Implementation of <a href="https://en.wikipedia.org/wiki/Kadane%27s_algorithm" target="_blank">Kadane Algorithm</a> </p>
<p>Kadane algorithm is used to find the maximum sum subarray in an array and maximum sum subarray problem is the task of finding a contiguous subarray with the largest sum</p>
<h3><a class="anchor" id="autotoc_md72"></a>
Algorithm</h3>
<p>The simple idea of the algorithm is to search for all positive contiguous segments of the array and keep track of maximum sum contiguous segment among all positive segments(curr_sum is used for this) Each time we get a positive sum we compare it with max_sum and update max_sum if it is greater than curr_sum</p>
<dl class="section author"><dt>Author</dt><dd><a href="https://github.com/ayush523" target="_blank">Ayush Singh</a> </dd></dl>
</div><h2 class="groupheader">Function Documentation</h2>
<a id="ae66f6b31b5ad750f1fe042a706a4e3d4" name="ae66f6b31b5ad750f1fe042a706a4e3d4"></a>
<h2 class="memtitle"><span class="permalink"><a href="#ae66f6b31b5ad750f1fe042a706a4e3d4">&#9670;&#160;</a></span>main()</h2>
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<td class="memname">int main </td>
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<td class="paramtype">void</td> <td class="paramname"><span class="paramname"><em></em></span></td><td>)</td>
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<p>Main function. </p>
<dl class="section return"><dt>Returns</dt><dd>0 on exit </dd></dl>
<div class="fragment"><div class="line"><span class="lineno"> 60</span> {</div>
<div class="line"><span class="lineno"> 61</span> <span class="keyword">const</span> <span class="keywordtype">int</span> <a class="code hl_variable" href="../../d6/d42/data__structures_2sparse__table_8cpp.html#a10f3ffb3f6f7e1b83d556b9c8de89a5d">N</a> = 5;</div>
<div class="line"><span class="lineno"> 62</span> <a class="code hl_classRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/array.html">std::array&lt;int, N&gt;</a> n{}; <span class="comment">// declaring array</span></div>
<div class="line"><span class="lineno"> 63</span> <span class="comment">// taking values of elements from user</span></div>
<div class="line"><span class="lineno"> 64</span> <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i = 0; i &lt; n.size(); i++) {</div>
<div class="line"><span class="lineno"> 65</span> <a class="code hl_classRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Enter value of n[&quot;</span> &lt;&lt; i &lt;&lt; <span class="stringliteral">&quot;]&quot;</span></div>
<div class="line"><span class="lineno"> 66</span> &lt;&lt; <span class="stringliteral">&quot;\n&quot;</span>;</div>
<div class="line"><span class="lineno"> 67</span> <a class="code hl_classRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_istream.html">std::cin</a> &gt;&gt; n[i];</div>
<div class="line"><span class="lineno"> 68</span> }</div>
<div class="line"><span class="lineno"> 69</span> <span class="keywordtype">int</span> max_sum = dynamic_programming::kadane::maxSubArray&lt;N&gt;(</div>
<div class="line"><span class="lineno"> 70</span> n); <span class="comment">// calling maxSubArray function</span></div>
<div class="line"><span class="lineno"> 71</span> <a class="code hl_classRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> &lt;&lt; <span class="stringliteral">&quot;Maximum subarray sum is &quot;</span> &lt;&lt; max_sum; <span class="comment">// Printing the answer</span></div>
<div class="line"><span class="lineno"> 72</span> </div>
<div class="line"><span class="lineno"> 73</span> <span class="keywordflow">return</span> 0;</div>
<div class="line"><span class="lineno"> 74</span>}</div>
<div class="ttc" id="aarray_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/container/array.html">std::array</a></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>
<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="adata__structures_2sparse__table_8cpp_html_a10f3ffb3f6f7e1b83d556b9c8de89a5d"><div class="ttname"><a href="../../d6/d42/data__structures_2sparse__table_8cpp.html#a10f3ffb3f6f7e1b83d556b9c8de89a5d">data_structures::sparse_table::N</a></div><div class="ttdeci">constexpr uint32_t N</div><div class="ttdoc">A struct to represent sparse table for min() as their invariant function, for the given array A....</div><div class="ttdef"><b>Definition</b> sparse_table.cpp:48</div></div>
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<h2 class="memtitle"><span class="permalink"><a href="#af3029007a422a914a85c0b0122f1c7b4">&#9670;&#160;</a></span>maxSubArray()</h2>
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template&lt;size_t N&gt; </div>
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<td class="memname">int dynamic_programming::kadane::maxSubArray </td>
<td>(</td>
<td class="paramtype">const <a class="elRef" target="_blank" href="http://en.cppreference.com/w/cpp/container/array.html">std::array</a>&lt; int, N &gt; &amp;</td> <td class="paramname"><span class="paramname"><em>n</em></span></td><td>)</td>
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<p>maxSubArray function is used to calculate the maximum sum subarray and returns the value of maximum sum which is stored in the variable max_sum </p>
<dl class="tparams"><dt>Template Parameters</dt><dd>
<table class="tparams">
<tr><td class="paramname">N</td><td>number of array size </td></tr>
</table>
</dd>
</dl>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">n</td><td>array where numbers are saved </td></tr>
</table>
</dd>
</dl>
<dl class="section return"><dt>Returns</dt><dd>the value of maximum subarray sum </dd></dl>
<div class="fragment"><div class="line"><span class="lineno"> 42</span> {</div>
<div class="line"><span class="lineno"> 43</span> <span class="keywordtype">int</span> curr_sum =</div>
<div class="line"><span class="lineno"> 44</span> 0; <span class="comment">// declaring a variable named as curr_sum and initialized it to 0</span></div>
<div class="line"><span class="lineno"> 45</span> <span class="keywordtype">int</span> max_sum = INT_MIN; <span class="comment">// Initialized max_sum to INT_MIN</span></div>
<div class="line"><span class="lineno"> 46</span> <span class="keywordflow">for</span> (<span class="keywordtype">int</span> i : n) { <span class="comment">// for loop to iterate over the elements of the array</span></div>
<div class="line"><span class="lineno"> 47</span> curr_sum += n[i];</div>
<div class="line"><span class="lineno"> 48</span> max_sum = <a class="code hl_functionRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/max.html">std::max</a>(max_sum, curr_sum); <span class="comment">// getting the maximum value</span></div>
<div class="line"><span class="lineno"> 49</span> curr_sum = <a class="code hl_functionRef" target="_blank" href="http://en.cppreference.com/w/cpp/algorithm/max.html">std::max</a>(curr_sum, 0); <span class="comment">// updating the value of curr_sum</span></div>
<div class="line"><span class="lineno"> 50</span> }</div>
<div class="line"><span class="lineno"> 51</span> <span class="keywordflow">return</span> max_sum; <span class="comment">// returning the value of max_sum</span></div>
<div class="line"><span class="lineno"> 52</span>}</div>
<div class="ttc" id="amax_html"><div class="ttname"><a href="http://en.cppreference.com/w/cpp/algorithm/max.html">std::max</a></div><div class="ttdeci">T max(T... args)</div></div>
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