#pragma once #include template , typename Alloc = std::allocator> using btree_set = phmap::btree_set; template , typename Alloc = std::allocator> using btree_multiset = phmap::btree_multiset; template , typename Alloc = std::allocator>> using btree_map = phmap::btree_map; template , typename Alloc = std::allocator>> using btree_multimap = phmap::btree_multimap;