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Documentation for c6af943508
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realstealthninja
@@ -114,17 +114,18 @@ $(function(){initNavTree('da/db8/count__of__set__bits_8cpp.html','../../'); init
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<p>Implementation to [count number of set bits of a number] (<a href="https://www.geeksforgeeks.org/count-set-bits-in-an-integer/">https://www.geeksforgeeks.org/count-set-bits-in-an-integer/</a>) in an integer.
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<a href="#details">More...</a></p>
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<div class="textblock"><code>#include <cassert></code><br />
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<code>#include <cstdint></code><br />
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<code>#include <iostream></code><br />
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</div><div class="textblock"><div class="dynheader">
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Include dependency graph for count_of_set_bits.cpp:</div>
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<div class="dyncontent">
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<div class="center"><iframe scrolling="no" frameborder="0" src="../../dd/d9f/count__of__set__bits_8cpp__incl.svg" width="171" height="126"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe></div>
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<div class="center"><iframe scrolling="no" frameborder="0" src="../../dd/d9f/count__of__set__bits_8cpp__incl.svg" width="255" height="126"><p><b>This browser is not able to show SVG: try Firefox, Chrome, Safari, or Opera instead.</b></p></iframe></div>
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</div>
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</div><table class="memberdecls">
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<tr class="heading"><td colspan="2"><h2 class="groupheader"><a id="namespaces" name="namespaces"></a>
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Namespaces</h2></td></tr>
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<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">namespace  </td><td class="memItemRight" valign="bottom"><a class="el" href="../../d7/d81/namespacebit__manipulation.html">bit_manipulation</a></td></tr>
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<tr class="memdesc:d7/d81/namespacebit__manipulation"><td class="mdescLeft"> </td><td class="mdescRight">for IO operations <br /></td></tr>
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<tr class="memdesc:d7/d81/namespacebit__manipulation"><td class="mdescLeft"> </td><td class="mdescRight">for assert <br /></td></tr>
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<tr class="separator:"><td class="memSeparator" colspan="2"> </td></tr>
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<tr class="memitem:"><td class="memItemLeft" align="right" valign="top">namespace  </td><td class="memItemRight" valign="bottom"><a class="el" href="../../dd/dae/namespacecount__of__set__bits.html">count_of_set_bits</a></td></tr>
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<tr class="memdesc:dd/dae/namespacecount__of__set__bits"><td class="mdescLeft"> </td><td class="mdescRight">Functions for the <a href="https://www.geeksforgeeks.org/count-set-bits-in-an-integer/" target="_blank">count sets bits</a> implementation. <br /></td></tr>
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@@ -171,21 +172,21 @@ Functions</h2></td></tr>
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</dd>
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</dl>
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<dl class="section return"><dt>Returns</dt><dd>total number of set-bits in the binary representation of number <code>n</code> </dd></dl>
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<div class="fragment"><div class="line"><span class="lineno"> 38</span> { <span class="comment">// int64_t is preferred over int so that</span></div>
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<div class="line"><span class="lineno"> 39</span> <span class="comment">// no Overflow can be there.</span></div>
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<div class="line"><span class="lineno"> 40</span> </div>
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<div class="line"><span class="lineno"> 41</span> <span class="keywordtype">int</span> count = 0; <span class="comment">// "count" variable is used to count number of set-bits('1')</span></div>
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<div class="line"><span class="lineno"> 42</span> <span class="comment">// in binary representation of number 'n'</span></div>
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<div class="line"><span class="lineno"> 43</span> <span class="keywordflow">while</span> (n != 0) {</div>
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<div class="line"><span class="lineno"> 44</span> ++count;</div>
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<div class="line"><span class="lineno"> 45</span> n = (n & (n - 1));</div>
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<div class="line"><span class="lineno"> 46</span> }</div>
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<div class="line"><span class="lineno"> 47</span> <span class="keywordflow">return</span> count;</div>
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<div class="line"><span class="lineno"> 48</span> <span class="comment">// Why this algorithm is better than the standard one?</span></div>
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<div class="line"><span class="lineno"> 49</span> <span class="comment">// Because this algorithm runs the same number of times as the number of</span></div>
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<div class="line"><span class="lineno"> 50</span> <span class="comment">// set-bits in it. Means if my number is having "3" set bits, then this</span></div>
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<div class="line"><span class="lineno"> 51</span> <span class="comment">// while loop will run only "3" times!!</span></div>
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<div class="line"><span class="lineno"> 52</span>}</div>
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<div class="fragment"><div class="line"><span class="lineno"> 39</span> { <span class="comment">// int64_t is preferred over int so that</span></div>
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<div class="line"><span class="lineno"> 40</span> <span class="comment">// no Overflow can be there.</span></div>
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<div class="line"><span class="lineno"> 41</span> </div>
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<div class="line"><span class="lineno"> 42</span> <span class="keywordtype">int</span> count = 0; <span class="comment">// "count" variable is used to count number of set-bits('1')</span></div>
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<div class="line"><span class="lineno"> 43</span> <span class="comment">// in binary representation of number 'n'</span></div>
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<div class="line"><span class="lineno"> 44</span> <span class="keywordflow">while</span> (n != 0) {</div>
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<div class="line"><span class="lineno"> 45</span> ++count;</div>
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<div class="line"><span class="lineno"> 46</span> n = (n & (n - 1));</div>
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<div class="line"><span class="lineno"> 47</span> }</div>
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<div class="line"><span class="lineno"> 48</span> <span class="keywordflow">return</span> count;</div>
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<div class="line"><span class="lineno"> 49</span> <span class="comment">// Why this algorithm is better than the standard one?</span></div>
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<div class="line"><span class="lineno"> 50</span> <span class="comment">// Because this algorithm runs the same number of times as the number of</span></div>
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<div class="line"><span class="lineno"> 51</span> <span class="comment">// set-bits in it. Means if my number is having "3" set bits, then this</span></div>
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<div class="line"><span class="lineno"> 52</span> <span class="comment">// while loop will run only "3" times!!</span></div>
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<div class="line"><span class="lineno"> 53</span>}</div>
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</div><!-- fragment --><div class="dynheader">
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Here is the call graph for this function:</div>
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<div class="dyncontent">
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@@ -211,10 +212,10 @@ Here is the call graph for this function:</div>
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<p>Main function. </p>
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<dl class="section return"><dt>Returns</dt><dd>0 on exit </dd></dl>
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<div class="fragment"><div class="line"><span class="lineno"> 79</span> {</div>
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<div class="line"><span class="lineno"> 80</span> test(); <span class="comment">// run self-test implementations</span></div>
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<div class="line"><span class="lineno"> 81</span> <span class="keywordflow">return</span> 0;</div>
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<div class="line"><span class="lineno"> 82</span>}</div>
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<div class="fragment"><div class="line"><span class="lineno"> 80</span> {</div>
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<div class="line"><span class="lineno"> 81</span> test(); <span class="comment">// run self-test implementations</span></div>
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<div class="line"><span class="lineno"> 82</span> <span class="keywordflow">return</span> 0;</div>
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<div class="line"><span class="lineno"> 83</span>}</div>
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</div><!-- fragment -->
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</div>
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</div>
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@@ -240,25 +241,25 @@ Here is the call graph for this function:</div>
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</tr>
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</table>
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</div><div class="memdoc">
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<div class="fragment"><div class="line"><span class="lineno"> 56</span> {</div>
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<div class="line"><span class="lineno"> 57</span> <span class="comment">// n = 4 return 1</span></div>
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<div class="line"><span class="lineno"> 58</span> assert(bit_manipulation::count_of_set_bits::countSetBits(4) == 1);</div>
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<div class="line"><span class="lineno"> 59</span> <span class="comment">// n = 6 return 2</span></div>
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<div class="line"><span class="lineno"> 60</span> assert(bit_manipulation::count_of_set_bits::countSetBits(6) == 2);</div>
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<div class="line"><span class="lineno"> 61</span> <span class="comment">// n = 13 return 3</span></div>
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<div class="line"><span class="lineno"> 62</span> assert(bit_manipulation::count_of_set_bits::countSetBits(13) == 3);</div>
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<div class="line"><span class="lineno"> 63</span> <span class="comment">// n = 9 return 2</span></div>
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<div class="line"><span class="lineno"> 64</span> assert(bit_manipulation::count_of_set_bits::countSetBits(9) == 2);</div>
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<div class="line"><span class="lineno"> 65</span> <span class="comment">// n = 15 return 4</span></div>
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<div class="line"><span class="lineno"> 66</span> assert(bit_manipulation::count_of_set_bits::countSetBits(15) == 4);</div>
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<div class="line"><span class="lineno"> 67</span> <span class="comment">// n = 25 return 3</span></div>
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<div class="line"><span class="lineno"> 68</span> assert(bit_manipulation::count_of_set_bits::countSetBits(25) == 3);</div>
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<div class="line"><span class="lineno"> 69</span> <span class="comment">// n = 97 return 3</span></div>
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<div class="line"><span class="lineno"> 70</span> assert(bit_manipulation::count_of_set_bits::countSetBits(97) == 3);</div>
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<div class="line"><span class="lineno"> 71</span> <span class="comment">// n = 31 return 5</span></div>
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<div class="line"><span class="lineno"> 72</span> assert(bit_manipulation::count_of_set_bits::countSetBits(31) == 5);</div>
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<div class="line"><span class="lineno"> 73</span> <a class="code hl_classRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> << <span class="stringliteral">"All test cases successfully passed!"</span> << <a class="code hl_functionRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/manip/endl.html">std::endl</a>;</div>
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<div class="line"><span class="lineno"> 74</span>}</div>
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<div class="fragment"><div class="line"><span class="lineno"> 57</span> {</div>
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<div class="line"><span class="lineno"> 58</span> <span class="comment">// n = 4 return 1</span></div>
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<div class="line"><span class="lineno"> 59</span> assert(bit_manipulation::count_of_set_bits::countSetBits(4) == 1);</div>
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<div class="line"><span class="lineno"> 60</span> <span class="comment">// n = 6 return 2</span></div>
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<div class="line"><span class="lineno"> 61</span> assert(bit_manipulation::count_of_set_bits::countSetBits(6) == 2);</div>
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<div class="line"><span class="lineno"> 62</span> <span class="comment">// n = 13 return 3</span></div>
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<div class="line"><span class="lineno"> 63</span> assert(bit_manipulation::count_of_set_bits::countSetBits(13) == 3);</div>
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<div class="line"><span class="lineno"> 64</span> <span class="comment">// n = 9 return 2</span></div>
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<div class="line"><span class="lineno"> 65</span> assert(bit_manipulation::count_of_set_bits::countSetBits(9) == 2);</div>
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<div class="line"><span class="lineno"> 66</span> <span class="comment">// n = 15 return 4</span></div>
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<div class="line"><span class="lineno"> 67</span> assert(bit_manipulation::count_of_set_bits::countSetBits(15) == 4);</div>
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<div class="line"><span class="lineno"> 68</span> <span class="comment">// n = 25 return 3</span></div>
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<div class="line"><span class="lineno"> 69</span> assert(bit_manipulation::count_of_set_bits::countSetBits(25) == 3);</div>
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<div class="line"><span class="lineno"> 70</span> <span class="comment">// n = 97 return 3</span></div>
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<div class="line"><span class="lineno"> 71</span> assert(bit_manipulation::count_of_set_bits::countSetBits(97) == 3);</div>
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<div class="line"><span class="lineno"> 72</span> <span class="comment">// n = 31 return 5</span></div>
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<div class="line"><span class="lineno"> 73</span> assert(bit_manipulation::count_of_set_bits::countSetBits(31) == 5);</div>
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<div class="line"><span class="lineno"> 74</span> <a class="code hl_classRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/basic_ostream.html">std::cout</a> << <span class="stringliteral">"All test cases successfully passed!"</span> << <a class="code hl_functionRef" target="_blank" href="http://en.cppreference.com/w/cpp/io/manip/endl.html">std::endl</a>;</div>
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<div class="line"><span class="lineno"> 75</span>}</div>
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<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>
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<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>
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</div><!-- fragment -->
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