What is a container in C? Are there any similarities and differences between containers and template

Containers are loaded with things, but according to the content and access methods of different containers, all kinds of containers have their advantages and disadvantages, so there are so many containers, these containers are STL's template library, which is part of the standard implementation, STL (Standard Template Library), just look at the name, it's all written by templates, templates and containers are not originally at the same level, they can't be compared, templates are like electricity, containers are TVs, and only when there is electricity can there be TVs.

Of course, you can write containers without templates, but the flexibility is relatively small, and it does not reflect the advantages of C++ templates.

A container is an imaginary entity that holds a class of data, a type of template class.

Templates are divided into template functions and template classes, the so-called template, is to give a solution that can be suitable for all types, given the template, there is no need to give the type of specific data, for example, vector can be filled with int, char and so on.

Not the same. Containers are generally used in STLs. The template itself can also be written, that is, the function method that the parameter type can be determined when it is called.

Containers in CPP are template classes defined in the Standard Template Library (STL).

The following types of containers are defined in the STL.

bitset,vector, list, stack,queue,deque,map,set,multimap,multiset

Containers: Template classes and libraries that can manipulate a variety of data structures and algorithms. It is possible to store various types of objects like a real-world container, and all objects in a container must be of the same type.

Container type: vector, list, deque, set, map, multiset, stack, queue, priority queue, and multimap.

Containers are used to store data, which can be of user-defined types (objects) or predefined types. Containers in C++ are mainly used such as vectors, lists (sequential containers) that are already encapsulated and contain header files"vector","list", access the data in the container through the iterator, map, set (associated container), the associated container map key-value pair appears in the form of key-value, the key is unique, and the mutimap multi-map can not be unique; A set is a collection of single values, such as 1, 2, 3, 4

Sequential containers: vector and list are examples for comparison.

For example, if a container with a capacity of 50 stores 60 string objects, because the initial capacity is less than 60, the container will redefine a new container with a capacity of 2 times the original capacity, and then copy the objects of the original container to the new container. The read speed is fast, and the insertion and deletion efficiency is low.

If you only add or delete changes to the head or tail of the container, it is recommended to use deque, which provides operations on the beginning and end.

List container features: Quite a linked list with a data structure, not a continuous storage area, it is easy to insert and delete, but the query speed is slow.

vectorvec defines a vector container that can be accessed.

push font(),insert(position,value) to add a specified value to the vector.

listilist《Initial size, default assignment》 listilist(20 -1) The initial 20 lists with a value of -1 are initial

Then the operation can refer to these methods of enveloping.

Associated containers: set map mutimap mutiset

key--> value.

set form 1234, the key value is unique;

You can call the member functions of a specific container.

The definition of a container in C++ is as follows: on the data store, there is an object type that can hold other objects or pointers to other objects, and this object type is called a container. In layman's terms, a container is an object that holds other objects, and this "object" also contains a number of columns of methods for dealing with other objects, which also reflects one of the benefits of container classes, "container classes are a good solution to specific reuse problems".

Another advantage of containers is that they can scale themselves, and the problem is that they don't know how many objects need to be stored, and arrays are lacking in this regard. Containers can request memory, free memory, and execute commands using optimal algorithms.

This usually refers to the C++ STL standard template library.

It provides a large number of containers to manage object groups, as well as standard algorithms, and these containers are added, deleted, modified, and searched, etc., and the time complexity is different, so suitable containers are needed.

These are all part of the C standard. Some containers may need to be supported by the C11 standard, but of course the compiler now generally supports it, so you can use it as you please.

Sequential containers. include to store arrays, queries and access are fast, adding and deleting is extremely slow. replaces arrays.

Include doubly linked lists, adding and removing them is fast, and queries and accesses are slow.

include double-headed queues, which are more like vectors than queues. Quick access, as well as quick insertion and deletion at both ends. But the insertion and deletion in the middle is slow.

The include size is fixed.

include a single necklace list, and the following is a simple interface built on a sequential container. Container adapters.

includeFirst-in, first-out, include each element has a priority, with unexpected queues, such as a VIP in the bank queue

First-in, first-out.

Other containers. include holds flag bits, no more bitwise operators. bitsetn indicates how many bits.

The container is associated with a key-value pair. (The key in the set is the value).

Include is faster than vector and slower than list. Lookups are faster than lists and slower than vectors. No duplication.

include allows duplicates.

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Unordered associated container hash table, (more appropriately called hash map, as is often called by third-party libraries).

#include

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