可以在c ++中使用字典

Question

I have been looking up dictionaries in C# and they seem to be highly useful, and was wondering if it is possible to use them in C++ as I have tried to search for dictionaries in C++ but there doesn't seem to be an equivalent that I can find. Is there some sort of library that I could download and include to the project or is there a function which does the same thing just with a different name.

Answer 1

There is a corresponding type in STL, that's called std::map .

It has the same basic functionality as a .NET Dictionary, but the implementation is quite different. std::map is internally based on a red-black tree datastructure, while Dictionary uses a hash table internally.

If you're just looking for something with the same behaviour, std::map will do, but if you have large amounts of data you have to be aware of the different performance characteristics.

Answer 2

对于对数访问时间（通常基于树实现）和std::unordered_map （自C ++ 11以来）的std::map用于预期的常量，最坏情况线性访问时间（通常基于散列实现）。

Answer 3

std :: map就像一个Dictionary 。

Answer 4

We can use map in C++ The basic format of using a map is -

    std::map<Key_type, Value_Type> ;

Example -

    std::map<std::string,std::string> x = {{"A","ABC"},{"B","DEF"}}