GF2::Vector — Index Locations
Returns the indices of the set or unset bits in a bit-vector.
std::vector<std::size_t> set_indices() const; (1)
std::vector<std::size_t> unset_indices() const; (2)| 1 | Returns the index locations of the set bits in order. |
| 2 | Returns the index locations of the unset bits in order. |
Example
#include <GF2/GF2.h>
#include <iterator>
int main()
{
auto v = GF2::Vector<>::checker_board(19); (1)
auto set_indices = v.set_indices();
auto unset_indices = v.unset_indices();
std::ostream_iterator<std::size_t> iter(std::cout," "); (2)
std::cout << "Bit-vector " << v << " has set indices at locations:\n";
std::copy (set_indices.begin(), set_indices.end(), iter);
std::cout << '\n';
std::cout << "Bit-vector " << v << " has unset indices at locations:\n";
std::copy (unset_indices.begin(), unset_indices.end(), iter);
std::cout << '\n';
}| 1 | Creates a checker board patterned bit-vector of size 19 and then extracts the set & unset index locations. |
| 2 | Use a stream iterator to print the those indices. |
Output
Bit-vector 0101010101010101010 has set indices at locations:
1 3 5 7 9 11 13 15 17
Bit-vector 0101010101010101010 has unset indices at locations:
0 2 4 6 8 10 12 14 16 18See Also