std::bitset<N>::set

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[edit]

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bitset::operator==bitset::operator!=

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bitset::allbitset::anybitset::none

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

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

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

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

1) Sets all bits totrue.

2) Sets the bit at positionpos to the valuevalue.

[edit]Parameters

pos	-	the position (counting from0, i.e. from least significant to most significant) of the bit to set
value	-	the value to set the bit to

[edit]Return value

*this

[edit]Exceptions

2) Throwsstd::out_of_range ifpos does not correspond to a valid bit position.

[edit]Example

Run this code

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

Output:

00000000111111110000000010101010

[edit]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 ofvalue wasint	corrected tobool
LWG 2250	C++98	the behavior was undefined ifpos does not correspond to a valid bit position	always throws an exception in this case