NAME¶

std::bitset::all,std::bitset::any,std::bitset::none - std::bitset::all,std::bitset::any,std::bitset::none

Synopsis¶

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.

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¶

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