Arrays, linked lists, jump table

Arrays, linked lists, jump table

Arrays, linked lists, and basically jump table properties

Array (Array)

• java, c ++: int a [100]; // initialization of the definition of a good capacity to
• Python: list = [] // define an array directly
• JavaScript: let x=[1,2,3]

time complexity

method	the complexity
prepend	O (n)
append	O (1)
lookup	O (1)
insert	O (n)
delete	O (n)

Member function

• Element access
  • access at specified element at the same time bounds checking
  • operator [] to access the specified element
  • front access to the first element
  • back to access the last element
  • It returns a pointer to the first data point in the array in memory element
• Iterator
  • begin the first element returns an iterator container
  • It returns a pointer to the tail end of the container end iterator
  • Returns a pointer to the last element of the container rbegin reverse iterator
  • Returns a pointer to the distal end rend reverse iterator
• capacity
  • Check whether the empty container is empty
  • Returns the size to accommodate the number of elements
  • max_size Returns the maximum number of elements that can be accommodated
• operating
  • fill the container filled with the specified value
  • swap exchange content

List

class Node {
    int data;
    Node next;
}
class LinkedList {
    Node head; /
    Node (int d) { data = d;}
}

time complexity

method	the complexity
prepend	O (1)
append	O (1)
lookup	O (n)
insert	O (1)
delete	O (1)

Member function

• Element access
  • front access to the first element
  • back to access the last element
• Iterator
  • Returns a pointer to the first element of the container begin iterator
  • It returns a pointer to the tail end of the container end iterator
  • Returns a pointer to the tail end of the container rbegin iterator
  • Returns a pointer to the distal end rend reverse iterator
• capacity
  • Check whether the empty container is empty
  • size Returns the number of receiving elements
  • max_size Returns the maximum number of elements that can be accommodated
• modifier
  • clear Clear content
  • insert insert elements
  • emplace situ construction elements
  • erase Erase element
  • push_back adding elements to the end of the container
  • emplace_back place at the end of the container construction element
  • pop_back end elements removed
  • the starting element is inserted into the container push_front
  • emplace_front container construction element head situ
  • pop_front remove the first element
  • resize can change the number of elements stored in the container
  • swap exchange content
• operating
  • merge merge two sorted list
  • splice elements move in list from another
  • remove / remove_if remove elements that meet specified criteria
  • The reverse order of all elements in the inverted list
  • unique erases consecutive duplicate elements
  • sort sorts the elements

Jump table

time complexity

• 跳表查询的时间复杂度分析：
  n/2、n/4、n/8、第k级索引结点的个数就是n/(2^k) 假设索引有h级，最高级的索引有2个结点。
  n/(2^h) = 2，从而求得 h = log2(n) - 1

• 时间复杂度 O(logn)
  • 优化
    • 升维 ：空间换时间
  • 应用
    • LRU Cache - Linked list: LRU 缓存机制

    • Redis - Skip LIst

      栈

      1.Stack：先入后出；添加、删除皆为O(1)
      2.查询为 O(n)

      时间复杂度

      方法	复杂度
      Access	O(n)
      Search	O(n)
      Insertion	O(1)
      Deletion	O(1)

      成员函数

• 元素访问
  • top 访问栈顶元素
• 容量
  • empty 检查底层的容器是否为空
  • size 返回容纳的元素数
• 修改器
  • push 向栈顶插入元素
  • emplace 于顶原位构造元素
  • pop 删除栈顶元素
  • swap 交换内容

队列

1.Queue：先入先出；添加、删除皆为O(1)
2.查询为 O(n)

时间复杂度

方法	复杂度
Access	O(n)
Search	O(n)
Insertion	O(1)
Deletion	O(1)

成员函数

• 元素访问
  • front 访问第一个元素
  • back 访问最后一个元素
• 容量
  • empty 检查底层的容器是否为空
  • size 返回容纳的元素数
• 修改器
  • push 像队列尾部插入元素
  • emplace 于尾部原位构造元素
  • pop 删除栈顶元素

  • swap 交换内容

    扩展

• 双端队列
  • 简单理解：两端可以进出的
  • 插入和删除都是O(1)操作
  • QueueDeque - double ended queue
• 优先队列
  • 插入操作：O(1)
  • 取出操作：O(logN) - 按照元素的优先级取出
  • 底层具体实现的数据结构较为多样和复杂：heap、bst(二叉搜索树)、treap