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std::rotr
Defined in header <bit> |
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(since C++20) |
Computes the result of bitwise right-rotating the value of x by s positions. This operation is also known as a right circular shift.
Formally, let N be std::numeric_limits<T>::digits, r be s % N.
- If
ris 0, returnsx; - if
ris positive, returns(x >> r) | (x << (N - r)); - if
ris negative, returnsstd::rotl(x, -r).
This overload participates in overload resolution only if T is an unsigned 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 right-rotating x by s positions.
Notes
| Feature-test macro | Value | Std | Feature |
|---|---|---|---|
__cpp_lib_bitops |
201907L | (C++20) | Bit operations |
Example
#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 << "rotr(i,0) = " << std::bitset<8>(std::rotr(i, 0)) << '\n';
std::cout << "rotr(i,1) = " << std::bitset<8>(std::rotr(i, 1)) << '\n';
std::cout << "rotr(i,9) = " << std::bitset<8>(std::rotr(i, 9)) << '\n';
std::cout << "rotr(i,-1) = " << std::bitset<8>(std::rotr(i, -1)) << '\n';
}
Output:
i = 00011101
rotr(i,0) = 00011101
rotr(i,1) = 10001110
rotr(i,9) = 10001110
rotr(i,-1) = 00111010
See also
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(C++20)
|
computes the result of bitwise left-rotation (function template) |
| performs binary shift left and shift right (public member function of std::bitset<N>) |
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