python data structures tutorial

1. ListPython has 6 built-in types of sequences, but the most common are lists and tuples.The operations that a sequence can perform include indexing, slicing, adding, multiplying, and checking members.In addition, Python has built-in methods for determining the length of the sequence and determining the maximum and bottom elements.A list is the most common type of Python

Python data structures and algorithms-algorithm analysisAn interesting problem often occurs, that is, two seemingly different programs. Which one is better? To answer this question, we must know that the program differs greatly from the algorithm representing the program. the algorithm is a general command that solves the problem. provides a solution to any insta

List of Python data structures and tuples Sequence: A sequence is a data structure that contains elements that are numbered (starting at 0). A typical sequence consists of a list, a string, and a tuple. Where the list is mutable (can be modified), and tuples and strings are immutable (once created are fixed). The s

Python cookbook (data structures and algorithms) keeps the dictionary orderly. This example describes how to keep the dictionary in order by using Python. We will share this with you for your reference. The details are as follows: Problem:When creating a dictionary and performing iteration or serialization operations o

Let's review the basic concepts of stacks and queues: The same point: from the "Data structure" point of view, they are all linear structures, that is, the relationship between the data elements is the same. The difference: A stack is a linear table that restricts insertions and deletions only at one end of the table. A queue is a linear table that qualifies onl

[3, 4, 5, 6, 7] 6 >>> Stack.pop () 7 7 8 >>> Stack 9 [3, 4, 5, 6]10 >>> stack.pop () 612 >>G T Stack.pop () 514 >>> stack15 [3, 4]Queue: FIFO1 >>> from collections import deque 2 >>> queue = Deque (["Eric", "John", "Michael"]) 3 >>> Queu E.append ("Terry") # Terry arrives 4 >>> queue.append ("Graham") # Graham arrives 5 >>> Queue.popleft () # The first to arrive now leaves 6 ' Eric ' 7 >>> queue.popleft () # The second to arrive no W leaves 8 '

This article mainly introduces the basic concepts of stack and queue data structures and related Python implementations. the knowledge of first-in-first-out and later-in-first-out has become a common topic in computer learning: d. you can refer to the following to review the basic concepts of stack and queue: Similarities: From the perspective of "

the old zoo. Back to the topic, notice that tuples within tuples do not lose their identities.You can access the items in a tuple by using a pair of parentheses to indicate the location of an item, just as we use the list. This is called the index operator. We use new_zoo[2] to access the third item in the New_zoo. We use new_zoo[2][2] to access the third item of the third project of the New_zoo tuple. Contains a tuple of 0 or 1 item objectives. An empty tuple consists of a pair of empty parent

Variables store the data in memory. This means that there is a space in memory when creating variables. Based on the data type of the variable, the interpreter allocates the specified memory and determines what data can be stored in memory.Variables in Python do not need to be declared , and the assignment of variables

Several data structures in the python collection module (Counter, OrderedDict, namedtup) The collection module has several data structures that we may use. Counter is a sub-class of the dictionary and is responsible for counting a dictionary. It supports + addition, subtract

'] = ' B ' dic[' c '] = ' c ' odic = ordereddict () odic[' a '] = ' a ' odic[' b '] = ' B ' odic[' c '] = ' C ' Print (' Unordered dictionary: ', dic) print (' Ordered dictionary: ', odic) print (' \ n ')Namedtup type, a dictionary-like tuple that can be converted to a dictionaryPrint (' Namedtup type application ') Deng = namedtuple (' Deng ', [' X ', ' y ']) i = Deng (x = 11,y = y) print (' I's value: ', i) print (' Add two values: ', i[0]+i [1]) Print (' Add by attribute: ', i.x+i.y) m,n = i

of the list without specifying indexSpecifies index, which pops an element from the index, and the index bounds throws a indexerror errorComplexity of Time:Do not specify an index of O (1)Specifies that the index is O (n) because subsequent elements may occur in memory after the insertion (the list is stored sequentially in memory)Clear (), NoneClears all elements of the list, leaving an empty listList Other actionsReverse ()-NoneReverses the list element, returning noneModify an existing objec

add subscribers to the class attribute X_lsit list, all Publishers share all subscribers.For example, Xiao Ming, small army subscribed to Cang teacher, small red small yellow to subscribe to the wave teacher, but Cang teacher update the film, due to share the subscribers, led to small red and small yellow also received new film notice, this is obviously a mistake.So Cang teacher and wave teacher X_list must be independent, need to write in __init__ inside, written self.x_list, so Cang teacher a

I. Data typeThere are six standard data types in Python: Number (numeric) String (String) List (lists) Tuple (tuple) Sets (collection) Dictionary (dictionary) In addition to the list and dictionary dictionaries, the data types are immutable data