C++

Reference

<bitset>

bitset

public member function
<bitset>

std::bitset::none

bool none() const;
bool none() const noexcept;
Test if no bit is set
Returns whether none of the bits is set (i.e., whether all bits in the bitset have a value of zero).

This is the opposite of bitset::any.

Parameters

none

Return value

true if none of the bits in the bitset is set (to one), and false otherwise.

Example

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// bitset::none
#include <iostream>       // std::cin, std::cout
#include <bitset>         // std::bitset

int main ()
{
  std::bitset<16> foo;

  std::cout << "Please, enter a binary number: ";
  std::cin >> foo;

  if (foo.none())
    std::cout << foo << " has no bits set.\n";
  else
    std::cout << foo << " has " << foo.count() << " bits set.\n";

  return 0;
}

Possible output:

Please, enter a binary number: 11010111
0000000011010111 has 6 bits set.


Data races

The bitset is accessed.

Exception safety

No-throw guarantee: never throws exceptions.

See also

bitset::count
Count bits set (public member function)
bitset::any
Test if any bit is set (public member function)
bitset::test
Return bit value (public member function)