I need to find the nearest keys in my map in a given range [x,y]. I am trying below

std::map<int, char> m{ {-2,'B'}, {1, 'C'},  {2, 'A'}};

auto itCurrent = m.lower_bound(-3);
auto itNext = m.upper_bound(-3);

auto it1 = m.lower_bound(3);
auto it2 = m.upper_bound(3);

I was hoping to get -2 and 2 by using lower_bound and uppper_bound around the enquiry boundary [-3,3]. it1 and it2 are returning end while itCurrent and itNext return -2.

How do I get -2 and 2 as result?