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std::bitset::count(3)	       C++ Standard Libary	   std::bitset::count(3)

NAME
     std::bitset::count - std::bitset::count

Synopsis
	std::size_t count() const;  (noexcept since C++11)
				    (constexpr since C++23)

	Returns the number of bits that are set to true.

Parameters
	(none)

Return value
	Number of bits that are set to true.

Example
     // Run this code

      #include <bitset>
      #include <iostream>

      int main()
      {
	  std::bitset<8> b("00010010");
	  std::cout << "Initial value: " << b << '\n';

	  // Find the first unset bit
	  std::size_t idx = 0;
	  while (idx < b.size() && b.test(idx))
	      ++idx;

	  // Continue setting bits until half the bitset is filled
	  while (idx < b.size() && b.count() < b.size() / 2)
	  {
	      b.set(idx);
	      std::cout << "Setting bit " << idx << ": " << b << '\n';
	      while (idx < b.size() && b.test(idx))
		  ++idx;
	  }

      }

Output:
      Initial value: 00010010
      Setting bit 0: 00010011
      Setting bit 2: 00010111

See also
	size	 returns the number of bits that the bitset holds
		 (public member function)
	popcount counts the number of 1 bits in an unsigned integer
	(C++20)  (function template)

http://cppreference.com 	   2024.06.10		   std::bitset::count(3)
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