std::bitset<N>::set

 

C++

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Feature test macros (C++20)

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Technical specifications

Symbols index

External libraries

 

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General utilities Date and time Function objects Formatting library (C++20) bitset hash (C++11) Relational operators (deprecated in C++20) rel_ops::operator!=rel_ops::operator> rel_ops::operator<=rel_ops::operator>= Integer comparison functions cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)    cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) Swap and type operations swap ranges::swap (C++20) exchange (C++14) declval (C++11) to_underlying (C++23) forward (C++11) forward_like (C++23) move (C++11) move_if_noexcept (C++11) as_const (C++17) Common vocabulary types pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) expected (C++23) Elementary string conversions to_chars (C++17) from_chars (C++17) chars_format (C++17)

 

std::bitset

Member types

bitset::reference

Member functions

bitset::bitset

bitset::operator==bitset::operator!= (until C++20)

Element access

bitset::operator[]

bitset::test

bitset::allbitset::anybitset::none (C++11)

bitset::count

Capacity

bitset::size

Modifiers

bitset::operator&=bitset::operator|=bitset::operator^=bitset::operator~

bitset::operator<<=bitset::operator>>=bitset::operator<<bitset::operator>>

bitset::set

bitset::reset

bitset::flip

Conversions

bitset::to_string

bitset::to_ulong

bitset::to_ullong (C++11)

Non-member functions

operator&operator|operator^

operator<<operator>>

Helper classes

std::hash (C++11)

 

	(1)
bitset& set();			(until C++11)
bitset& set() noexcept;			(since C++11) (until C++23)
constexpr bitset& set() noexcept;			(since C++23)
		(2)
bitset& set( std::size_t pos, bool value = true );				(until C++23)
constexpr bitset& set( std::size_t pos, bool value = true );				(since C++23)

Sets all bits to true or sets one bit to specified value.

1) Sets all bits to true.

2) Sets the bit at position pos to the value value.

Parameters

pos	-	the position (counting from 0, from least significant to most significant) of the bit to set
value	-	the value to set the bit to

Return value

*this

Exceptions

2) Throws std::out_of_range if pos does not correspond to a valid position within the bitset.

Example

Run this code

#include <iostream>
#include <bitset>
 
int main()
{
    std::bitset<8> b;
    std::cout << b << '\n';
    std::cout << b.set() << '\n';
    std::cout << b.reset() << '\n';    
 
    for (size_t i = 1; i < b.size(); i += 2)
        b.set(i);
 
    std::cout << b << '\n';
}

Output:

00000000
11111111
00000000
10101010

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 186	C++98	the type of value was int	corrected to bool

See also

reset	sets bits to false (public member function)
flip	toggles the values of bits (public member function)