std::bitset<N>::flip

bitset& flip();	(1)	(noexcept since C++11) (constexpr since C++23)
bitset& flip( std::size_t pos ) ;	(2)	(constexpr since C++23)

Flips bits, i.e. changes true values to false and false values to true

1) Flips all bits (like operator~, but in-place).

2) Flips the bit at the position pos.

Parameters

pos

-

the position of the bit to flip

Return value

*this

Exceptions

2) Throws std::out_of_range if pos

Example

Run this code

#include <bitset>
#include <iostream>
 
int main()
{
    std::bitset<4> flops;
 
    std::cout << flops << '\n'
              << flops.flip(0) << '\n'
              << flops.flip(2) << '\n'
              << flops.flip() << '\n';
}

Output:

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2250	C++98	the behavior was undefined if pos does not correspond to a valid bit position	always throws an exception in this case

Compiler support
Freestanding and hosted
Language
Standard library
Standard library headers
Named requirements
Feature test macros (C++20)
Language support library
Concepts library (C++20)
Diagnostics library
Memory management library
Metaprogramming library (C++11)
General utilities library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Strings library
Text processing library
Numerics library
Date and time library
Input/output library
Filesystem library (C++17)
Concurrency support library (C++11)
Execution support library (C++26)
Technical specifications
Symbols index
External libraries

set	sets bits to true or given value (public member function)
reset	sets bits to false (public member function)
operator&=operator\|=operator^=operator~	performs binary AND, OR, XOR and NOT (public member function)
flip	flips all the bits (public member function of `std::vector<bool,Allocator>`)