STL:
1.containers: (class template)
a.sequence container. vector,list,deque
b.associative container. set.map.(multi set. multi map)
*sorted container. set.pri-queue(adapter for deque).map.
2.algorithms.(fun template)
3.iterator. (重载了*,->的class template)
4.function.(仿函数)重载了operator() 的class template.
5.adaptor. (container | function | iterator adapter)
stack, queue.
6.allocators: