August 2021
Intermediate to advanced
450 pages
5h 35m
Chinese
Content preview from C++语言导学（原书第2版）
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11.2.1 元素
类似所有标准库容器，vector是某种类型为T的元素的容器，即vector<T>。几乎任何类型都可以作为元素类型：内置数值类型（如char、int和double）、用户自定义类型（如string、Entry、list<int>和Matrix<double，2>）以及指针类型（如const char*、Shape*和double*）。当你插入一个新元素时，它的值被拷贝到容器中。例如，当你将一个整型值7存入容器，结果元素确实就是一个值为7的整型对象，而不是指向某个整型对象7的引用或指针。这样的策略促成了精巧、紧凑、访问快速的容器。对于在意内存大小和运行时性能的人，这是非常关键的。
如果你有一个类层次（参见4.5节），它可依赖virtual函数获得多态性，就不应在容器中直接保存对象，而应保存对象的指针（或智能指针，参见13.2.1节）。例如：
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.