bit_floor()

#include <bit>

int bit_floor (T x)

Liefert die nächstkleinere Zweierpotenz (falls x selbst keine ist).

Rückgabewert: Zweierpotenz, falls x != 0, sonst 0.

bit_ceil(), has_single_bit().

bit.cpp

#include <bit>
#include <iostream>
 
int main()
{
  auto n = 42u;
 
  std::cout << std::has_single_bit(n) << '\n';
  std::cout << std::bit_ceil(n) << '\n';
  std::cout << std::bit_floor(n) << '\n';
  std::cout << std::bit_width(n) << '\n';
 
  std::cout << std::rotl(n, 8) << '\n';
  std::cout << std::rotr(n, 8) << '\n';
 
  std::cout << std::countl_zero(n) << '\n';
  std::cout << std::countl_one(n) << '\n';
  std::cout << std::countr_zero(n) << '\n';
  std::cout << std::countr_one(n) << '\n';
 
  std::cout << std::popcount(n) << '\n';
}