问题
assume that we have a data1
and data2
. How can I intersect them with std::set_intersect()
?
struct pID
{
int ID;
unsigned int IDf;// postition in the file
pID(int id,const unsigned int idf):ID(id),IDf(idf){}
bool operator<(const pID& p)const { return ID<p.ID;}
};
struct ID{};
struct IDf{};
typedef multi_index_container<
pID,
indexed_by<
ordered_unique<
tag<IDf>, BOOST_MULTI_INDEX_MEMBER(pID,unsigned int,IDf)>,
ordered_non_unique<
tag<ID>,BOOST_MULTI_INDEX_MEMBER(pID,int,ID)> >
> pID_set;
ID_set data1, data2;
Load(data1); Load(data2);
pID_set::index<ID>::type& L1_ID_index=L1.data.get<ID>();
pID_set::index<ID>::type& L2_ID_index=L2.data.get<ID>();
// How do I use set_intersect?
回答1:
std::set_intersection(
L1_ID_index.begin(),L1_ID_index.end(),
L2_ID_index.begin(),L2_ID_index.end(),
output_iterator,
L1_ID_index.value_comp());
来源:https://stackoverflow.com/questions/2448058/boost-multiindex-how-to-make-an-effective-set-intersection