operator<<,>>(std::bitset)

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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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operator<<operator>>

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Defined in header`<bitset>`
template<class CharT,class Traits,std::size_t N> std::basic_ostream<CharT, Traits>& operator<<(std::basic_ostream<CharT, Traits>& os,conststd::bitset<N>& x);	(1)
template<class CharT,class Traits,std::size_t N> std::basic_istream<CharT, Traits>& operator>>(std::basic_istream<CharT, Traits>& is,std::bitset<N>& x);	(2)

Inserts or extracts a bitset from a character stream.

1) Writes the bitsetx to the character streamos as if by first converting it to astd::basic_string<CharT, Traits> usingto_string(), and then writing it intoos using theoperator<< (which is aFormattedOutputFunction for strings).
The characters to use for ones and zeroes are obtained from the currently-imbued locale by callingstd::use_facet<std::ctype<CharT>>(os.getloc()).widen() with'1' and'0' as arguments.

2) Behaves as aFormattedInputFunction. After constructing and checking the sentry object, which may skip leading whitespace, extracts up toN characters fromis and stores the characters in the bitsetx.
Characters are extracted until either

N characters have been read,
end-of-file occurs inis, or
the next character is neitheris.widen('0') noris.widen('1').

IfN>0 and no characters are extracted,is.setstate(ios_base::failbit) is called.

[edit]Parameters

os	-	the character stream to write to
is	-	the character stream to read from
x	-	the bitset to be read or written

[edit]Return value

1)os

2)is

[edit]Example

Run this code

#include <bitset>#include <iostream>#include <sstream> int main(){std::string bit_string="001101";std::istringstream bit_stream(bit_string); std::bitset<3> b1;    bit_stream>> b1;// reads "001", stream still holds "101"std::cout<< b1<<'\n'; std::bitset<8> b2;    bit_stream>> b2;// reads "101", populates the 8-bit set as "00000101"std::cout<< b2<<'\n';}

Output:

00100000101

[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 303	C++98	single-byte characters were extracted from is, but`CharT` can have multiple bytes	extracts`CharT` and compares it with widened'0' and'1'
LWG 396	C++98	the content written byoperator<< was locale-independent	writes widened'0's and'1's
LWG 3199	C++98	extracting a`std::bitset<0>` always sets`failbit`	such extraction never sets`failbit`