C++中的一组集合

Question

如何在C++中创建一组集合？

set<char> inner1;
set<char> inner2;
set< set<char> > outer;
set< set<char> >:: iterator new_it;
set<char>::iterator it;

for (int i = 65; i < 70; ++i)
    inner1.insert(i);

for (int i = 70; i < 80; ++i)
    inner2.insert(i);

outer.insert(inner1);
outer.insert(inner2);

for(new_it=outer.begin();new_it!=outer.end();new_it++)
{
   for(it=*(new_it);it!=(new_it);)
   {

   }
}

Answer 1

您不能分配new_it到it在内部循环.这样做:

for(it = new_it->begin(); it!=new_it->end(); ++it)