STL之关联容器(set /map /multiset /multimap)

资料备份

关联容器一般以平衡二叉搜索树作为内部数据结构,RB-tree的应用尤其广泛。
RB-tree
是许多平衡二叉查找树的一种,一颗有n个内结点的红黑树的高度至多为2lg(n+1),

它能保证在最坏情况下,基本的动态集合操作时间为O(lgn)。

关联容器支持通过键来高效地查找和读取元素,两个基本的关联容器是map和set。

set仅包含一个键,并有效地支持关于某个键是否存在的查询。

map的元素是“键-值”对的二元组形式:键用作元素在map中的索引,而值则表示所存储和读取的数据

set和map类型的对象所包含的元素都具有不同的键。如果需要一个键对应多个实例,则需要使用multimap或multiset类型

具体的操作:

和顺序容器相比不支持元素访问的操作像front,back,at,operater[],

不支持修改器中的 asign ,pop_back,pop_front,push_front,push_back也不支持resize

还有顺序容器没有的key_comp,value_comp,find,count,lower_bound,upper_bound,equal_range 操作

学习资料记录:

STL 各容器对比表

Sequence containers

Associative containers

Headers

<vector>

<deque>

<list>

<set>

<bitset>

Members

complex

vector

deque

list

set

multiset

map

multimap

bitset

constructor

*

constructor

constructor

constructor

constructor

constructor

constructor

constructor

constructor

destructor

O(n)

destructor

destructor

destructor

destructor

destructor

destructor

destructor

operator=

O(n)

operator=

operator=

operator=

operator=

operator=

operator=

operator=

operators

iterators

begin

O(1)

begin

begin

begin

begin

begin

begin

begin

end

O(1)

end

end

end

end

end

end

end

rbegin

O(1)

rbegin

rbegin

rbegin

rbegin

rbegin

rbegin

rbegin

rend

O(1)

rend

rend

rend

rend

rend

rend

rend

capacity

size

*

size

size

size

size

size

size

size

size

max_size

*

max_size

max_size

max_size

max_size

max_size

max_size

max_size

empty

O(1)

empty

empty

empty

empty

empty

empty

empty

resize

O(n)

resize

resize

resize

element access

front

O(1)

front

front

front

back

O(1)

back

back

back

operator[]

*

operator[]

operator[]

operator[]

operator[]

at

O(1)

at

at

modifiers

assign

O(n)

assign

assign

assign

insert

*

insert

insert

insert

insert

insert

insert

insert

erase

*

erase

erase

erase

erase

erase

erase

erase

swap

O(1)

swap

swap

swap

swap

swap

swap

swap

clear

O(n)

clear

clear

clear

clear

clear

clear

clear

push_front

O(1)

push_front

push_front

pop_front

O(1)

pop_front

pop_front

push_back

O(1)

push_back

push_back

push_back

pop_back

O(1)

pop_back

pop_back

pop_back

observers

key_comp

O(1)

key_comp

key_comp

key_comp

key_comp

value_comp

O(1)

value_comp

value_comp

value_comp

value_comp

operations

find

O(log n)

find

find

find

find

count

O(log n)

count

count

count

count

count

lower_bound

O(log n)

lower_bound

lower_bound

lower_bound

lower_bound

upper_bound

O(log n)

upper_bound

upper_bound

upper_bound

upper_bound

equal_range

O(log n)

equal_range

equal_range

equal_range

equal_range

unique members

capacity
reserve

splice
remove
remove_if
unique
merge
sort
reverse

set
reset
flip
to_ulong
to_string
test
anynone

简单的例子:

http://developer.51cto.com/art/201107/275765.htm

夜风总结

http://blog.csdn.net/yfkiss/article/category/826423

jiahehao:

http://blog.csdn.net/jiahehao/article/category/342088

网站推荐:

http://www.cplusplus.com/

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