(1) | ||
bool operator[]( std::size_t pos ) const; | (until C++11) | |
constexpr bool operator[]( std::size_t pos ) const; | (since C++11) | |
reference operator[]( std::size_t pos ); | (2) |
Accesses the bit at position pos
. The first version returns the value of the bit, the second version returns an object of type std::bitset::reference
that allows modification of the value.
Unlike test()
, does not throw exceptions: the behavior is undefined if pos
is out of bounds.
pos | - | position of the bit to return |
1) the value of the requested bit.
2) an object of type std::bitset::reference
, which allows writing to the requested bit.
None.
#include <iostream> #include <bitset> int main() { std::bitset<8> b1(42); for (std::size_t i = 0; i < b1.size(); ++i) { std::cout << "b1[" << i << "]: " << b1[i] << '\n'; } b1[0] = true; // modifies the first bit through bitset::reference std::cout << "After setting bit 0, the bitset holds " << b1 << '\n'; }
Output:
b1[0]: 0 b1[1]: 1 b1[2]: 0 b1[3]: 1 b1[4]: 0 b1[5]: 1 b1[6]: 0 b1[7]: 0 After setting bit 0, the bitset holds 00101011
accesses specific bit (public member function) |
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