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std::rotl(3)		       C++ Standard Libary		    std::rotl(3)

NAME
     std::rotl - std::rotl

Synopsis
	Defined in header <bit>
	template< class T >					(since C++20)
	[[nodiscard]] constexpr T rotl( T x, int s ) noexcept;

	Computes  the  result of bitwise left-rotating the value of x by s posi-
     tions. This
	operation is also known as a left circular shift.

	Formally, let N be std::numeric_limits<T>::digits, r be s % N.

	  * If r is 0, returns x;
	  * if r is positive, returns (x << r) | (x >> (N - r));
	  * if r is negative, returns std::rotr(x, -r).

	This overload participates in overload resolution only if T  is  an  un-
     signed integer
	type  (that  is,  unsigned  char, unsigned short, unsigned int, unsigned
     long, unsigned
	long long, or an extended unsigned integer type).

Parameters
	x - value of unsigned integer type
	s - number of positions to shift

Return value
	The result of bitwise left-rotating x by s positions.

Notes
	Feature-test macro  Value    Std      Feature
	__cpp_lib_bitops   201907L (C++20) Bit operations

Example
     // Run this code

      #include <bit>
      #include <bitset>
      #include <cstdint>
      #include <iostream>

      int main()
      {
	  const std::uint8_t i = 0b00011101;
	  std::cout << "i	   = " << std::bitset<8>(i) << '\n';
	  std::cout << "rotl(i,0)  = "	<<  std::bitset<8>(std::rotl(i,  0))  <<
     '\n';
	  std::cout  <<  "rotl(i,1)   =  " << std::bitset<8>(std::rotl(i, 1)) <<
     '\n';
	  std::cout << "rotl(i,4)  = "	<<  std::bitset<8>(std::rotl(i,  4))  <<
     '\n';
	  std::cout  <<  "rotl(i,9)   =  " << std::bitset<8>(std::rotl(i, 9)) <<
     '\n';
	  std::cout << "rotl(i,-1) = " <<  std::bitset<8>(std::rotl(i,	-1))  <<
     '\n';
      }

Output:
      i 	 = 00011101
      rotl(i,0)  = 00011101
      rotl(i,1)  = 00111010
      rotl(i,4)  = 11010001
      rotl(i,9)  = 00111010
      rotl(i,-1) = 10001110

See also
	rotr	    computes the result of bitwise right-rotation
	(C++20)     (function template)
	operator<<=
	operator>>= performs binary shift left and shift right
	operator<<  (public member function of std::bitset<N>)
	operator>>

http://cppreference.com 	   2024.06.10			    std::rotl(3)
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