std::bitset<N>:: to_string

From cppreference.com

	(1)
template < class CharT, class Traits, class Allocator > std:: basic_string < CharT, Traits, Allocator > to_string ( CharT zero = CharT ( '0' ) , CharT one = CharT ( '1' ) ) const ;			(until C++11)
template < class CharT = char , class Traits = std:: char_traits < CharT > , class Allocator = std:: allocator < CharT > > std:: basic_string < CharT, Traits, Allocator > to_string ( CharT zero = CharT ( '0' ) , CharT one = CharT ( '1' ) ) const ;			(since C++11) (constexpr since C++23)
template < class CharT, class Traits > std:: basic_string < CharT, Traits > to_string ( CharT zero = CharT ( '0' ) , CharT one = CharT ( '1' ) ) const ;		(2)	(until C++11)
template < class CharT > std:: basic_string < CharT > to_string ( CharT zero = CharT ( '0' ) , CharT one = CharT ( '1' ) ) const ;		(3)	(until C++11)
std:: string to_string ( char zero = '0' , char one = '1' ) const ;		(4)	(until C++11)

Converts the contents of the bitset to a string. Uses zero to represent bits with value of false and one to represent bits with value of true .

The resulting string contains N characters with the first character corresponds to the last ( N - 1 ^th ) bit and the last character corresponding to the first bit.

All template type arguments need to be provided because function templates cannot have default template arguments. Overloads (2-4) are provided to simplify the invocations of to_string :

2) Uses the default allocator std::allocator .

3) Uses the default character trait std::char_traits and the default allocator std::allocator .

4) Uses the default character type char , the default character trait std::char_traits and the default allocator std::allocator .

(until C++11)

Parameters

zero	-	character to use to represent false
one	-	character to use to represent true

Return value

1) The converted string.

2) to_string < CharT, Traits, std:: allocator < CharT >> ( zero, one ) .

3) to_string < CharT, std:: char_traits < CharT > , std:: allocator < CharT >> ( zero, one ) .

4) to_string < char , std:: char_traits < char > , std:: allocator < char >> ( zero, one ) .

Exceptions

May throw std::bad_alloc from the std::basic_string constructor.

Notes

Since C++11, functions templates can have default template arguments. LWG issue 1113 removed the helper overloads ( 2-4 ) and added the corresponding default template arguments in ( 1 ) .

Example

Run this code

#include <bitset>
#include <iostream>
 
int main()
{
    std::bitset<8> b{42};
    std::cout << b.to_string() << '\n'
              << b.to_string('*') << '\n'
              << b.to_string('O', 'X') << '\n';
}

Output:

00101010
**1*1*1*
OOXOXOXO

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 396	C++98	zero and one bits were converted to characters 0 and 1 (which do not correspond to '0' and '1' )	added parameters to provide values for these characters
LWG 434	C++98	all template arguments needed to be provided	added overloads ( 2-4 )
LWG 853	C++98	overloads ( 2-4 ) did not have the default arguments added by LWG issue 396	also added

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)
Metaprogramming library (C++11)
Diagnostics library
General utilities library
Strings library
Containers library
Iterators library
Ranges library (C++20)
Algorithms library
Numerics library
Localizations library
Input/output library
Filesystem library (C++17)
Regular expressions library (C++11)
Concurrency support library (C++11)
Execution support library (C++26)
Technical specifications
Symbols index
External libraries

to_ulong	returns an unsigned long integer representation of the data (public member function)
to_ullong (C++11)	returns an unsigned long long integer representation of the data (public member function)