Iterator 是 STL 的核心抽象接口 | STL
本章覆盖：iterator as generalized pointer；dereference；increment；equality；begin；end；half-open range；container / algorithm decoupling；iterator value type；algorithms consume iterator ranges；STL 泛型体系的真正连接层。
本章知识点
- iterator as generalized pointer
- dereference
- increment
- equality
- begin
- end
- half-open range
- container / algorithm decoupling
- iterator value type
- algorithms consume iterator ranges
- STL 泛型体系的真正连接层