Namespaces
Variants

std::bitset<N>:: all, std::bitset<N>:: any, std::bitset<N>:: none

From cppreference.net
C++
Utilities library
std::bitset
bool all ( ) const ;
(1) (noexcept since C++11)
(constexpr since C++23)
bool any ( ) const ;
(2) (noexcept since C++11)
(constexpr since C++23)
bool none ( ) const ;
(3) (noexcept since C++11)
(constexpr since C++23)
1) Checks if all bits are set to true .
2) Checks if any bits are set to true .
3) Checks if none of the bits are set to true .

Contents

Parameters

(none)

Return value

1) true if all bits are set to true , otherwise false .
2) true if any of the bits are set to true , otherwise false .
3) true if none of the bits are set to true , otherwise false .

Example

Run this code 
#include <bitset>
#include <iostream>
int main()
{
    std::bitset<4> b1("0000");
    std::bitset<4> b2("0101");
    std::bitset<4> b3("1111");
    std::cout
        << "bitset\t" << "all\t" << "any\t" << "none\n"
        << b1 << '\t' << b1.all() << '\t' << b1.any() << '\t' << b1.none() << '\n'
        << b2 << '\t' << b2.all() << '\t' << b2.any() << '\t' << b2.none() << '\n'
        << b3 << '\t' << b3.all() << '\t' << b3.any() << '\t' << b3.none() << '\n';
}

Output: 

bitset  all any none
0000    0   0   1
0101    0   1   0
1111    1   1   0

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 693 C++98 the member function all() was not provided provided

See also

returns the number of bits set to true
(public member function)
(C++20)
counts the number of 1 bits in an unsigned integer
(function template)