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

(1) 
bool all() const;
 (until C++11) 
bool all() const noexcept;
 (since C++11)
(constexpr since C++23)
(2) 
bool any() const;
 (until C++11) 
bool any() const noexcept;
 (since C++11)
(constexpr since C++23)
(3) 
bool none() const;
 (until C++11) 
bool none() const 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.

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

#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)

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