std::bitset::bitset
constexpr bitset() noexcept; |
(1) | |
constexpr bitset(unsigned long long val) noexcept; |
(2) | |
template< class CharT, class Traits, class Allocator > explicit bitset( const std::basic_string<CharT,Traits,Allocator>& str, |
(3) | (until C++11) (since C++11) |
template< class CharT > explicit bitset( const CharT* str, |
(4) | (since C++11) |
Constructs a new bitset from one of several optional data sources:
1. Default constructor. Constructs a bitset with all bits set to zero.
2. Constructs a bitset using the bits in val. If the N is the size of the bitset and M is the number of set bits in val, then only min(N, M) bits will be included in the bitset.
3. Constructs a bitset using the characters in the std::basic_string str. An optional starting position pos and length n can be provided, as well as characters denoting alternate values for set (one) and unset (zero) bits.
The effective length of the initializing string is min(n, str.size() - pos).
If pos > str.size(), this constructor throws std::out_of_range. If any characters examined in str are not zero or one, it throws std::invalid_argument.
4. Similar to (3), but uses a CharT* instead of a std::basic_string.
[edit] Parameters
val | - | number used to initialize the bitset |
str | - | string used to initialize the bitset |
pos | - | a starting offset into str |
n | - | number of characters to use from str |
one | - | alternate character for set bits in str |
zero | - | alternate character for unset bits in str |
[edit] Example
#include <bitset> #include <string> int main() { // empty constructor std::bitset<8> b1; // [0,0,0,0,0,0,0,0] // unsigned long long constructor std::bitset<8> b2(42); // [0,0,1,0,1,0,1,0] // string constructor std::string bit_string = "110010"; std::bitset<8> b3(bit_string); // [0,0,1,1,0,0,1,0] std::bitset<8> b4(bit_string, 2); // [0,0,0,0,0,0,1,0] std::bitset<8> b5(bit_string, 2, 3); // [0,0,0,0,0,0,0,1] // string constructor using custom zero/one digits std::string alpha_bit_string = "aBaaBBaB"; std::bitset<8> b6(alpha_bit_string, 0, alpha_bit_string.size(), 'a', 'B'); // [0,1,0,0,1,1,0,1] // char* constructor using custom digits std::bitset<8> b7("XXXXYYYY", 0, 'X', 'Y'); // [0,0,0,0,1,1,1,1] return 0; }
[edit] See also
sets bits to true or given value (public member function) | |
sets bits to false (public member function) |