data structures and algorithms books

① problem: If there is a tuple or sequence containing n multiple elements, now you want to break it down into n separate variables. 1 L = (4, 5)2 x, y = lView Code② Advanced article:data = ['sb' ' big hammer ', (2018, 6, 2 = dataa='sb'b=' big hammer ' C=51Date= (2018, 6, 2)③data = ['sb' ' big hammer ', (2018, 6, 2 == 2018= 6= 2View CodeSo then the question comes, this is to know the list of how much of the situation to achieve, if the unknown? that

numbering unit 　　You can use the stack to do 10-in-2~9 binary operationsHere's how: a decimal number A, binary B1> will a%b, press into the stack2> Replace A with A/b3> if a is greater than 0, continue to hit 1> repeatedlyIf it is less than 0, jump out4> the elements of the stack pop up once, forming a new character (the character is the result of conversion completion)As an example:　　10 to 2 binary:10%2 = 0--into the stack--05%2 =--1 in the stack, 02%2 = 0--into the stack--0, 1, 01%2 =--1 in s

1. Code implementationdefMerge_sort (alist):ifLen (alist) : returnalist#two-part decompositionnum = Len (alist)/2 Left=Merge_sort (Alist[:num]) right=Merge_sort (alist[num:])#Merging returnmerge (Left,right)defmerge (left, right):" "merge operation, combine two ordered arrays left[] and right[] into a large ordered array" " #The subscript pointer to left and rightL, R =0, 0 result= [] whileL andrLen (right):ifLEFT[L] Right[r]: Result.append (Left[l]) L+ = 1Else: Result.append (R

1. How to find two pointsFind the fastest speed for a sorted list2. Code implementation(1) Recursive implementationdefBinary_search (Alist, item):ifLen (alist) = =0:returnFalseElse: Midpoint= Len (alist)//2ifalist[midpoint]==Item:returnTrueElse: ifitemAlist[midpoint]:returnBinary_search (Alist[:midpoint],item)Else: returnBinary_search (alist[midpoint+1:],item) testlist= [0, 1, 2, 8, 13, 17, 19, 32, 42,]Print(Binary_search (Testlist, 3))Print(Binary_search (Testlist, 13))(2) N

1. Principle:2. Code implementationdefQuick_sort (alist, Start, end):"""Quick Sort""" #Recursive exit conditions ifStart >=End:return #sets the starting element as the datum element to find the positionMID =Alist[start]#Low is the left-to-right cursor for the left of the sequenceLow =Start#High is the right-to-left cursor to the right of the sequenceHigh =End whileLow High :#If low is not coincident with high, the element with high points is not smaller than the datum element, then high

1. Basic properties of stacks and queues Stack is advanced after out; (like a bullet clip, a last-shot first) Queues are FIFO; (like waiting in line to buy ice cream, in order to take turns) Stack and queue in the implementation of the structure can have an array and a list of two forms; (1) The array structure is easy to implement;(2) The structure of the linked list is more complicated, because it involves a lot of pointer operation;1.1 Basic operation of stack structure(1) Pop op

()) { CharCH =Thestack.pop (); Output= output +ch; } returnoutput; } } classReverseapp { Public Static voidMain (string[] args)throwsIOException {String input, output; while(true) {System.out.print ("Enter A string:"); System.out.flush (); Input=getString1 (); if(Input.equals ("")) { Break; } reverser Thereverser=Newreverser (input); Output=Thereverser.dorev (); System.out.println ("Reversed:" +output); } } Public StaticString getString

value.Similarly, when an element of the RightMark position is greater than or equal to the base value, RightMark moves to the left one position to continue scanning, and the scan stops when the element of the RightMark position is less than the base value.After stopping the scan, we compare the size of the Leftmark and RightMark, if the Rightmark　　After we have put the datum values in the correct position, we see that the elements on the left side of the base value are smaller than the datum va

"Select Sort"The selection sort is based on a bubbling sort (Bubble sort) that has been improved: each visit process (pass) needs to be exchanged at most.Each visit process, to find the maximum value, when the end of the visit, the maximum value is exchanged to the correct position;Then continue to repeat the process in the remaining sublist until the n-1 visit is completed (n is the length of the list);At this point, the remaining elements in the list are automatically aligned to the correct po

= [] showing the same gender; Let len = this.list.length; while (len--) {if (This.list[len].gender = = = Gender) {Ret.push (this.list[len].name); }} return ret;} Example let people = new person ();p eople.save (' Mazey ', ' Male ');p eople.save (' John ', ' Male ');p eople.save (' Zero ', ' Male '); People.save (' July ', ' Male ');p eople.save (' Bob ', ' Male ');p eople.save (' Ada ', ' female ');p eople.save (' Cherrie ', ' female ');p eople.save (' Luna ', ' female ');p eople.save

This article illustrates the fast sequencing of data structures and algorithms implemented by Python. Share to everyone for your reference. The specific analysis is as follows: I. Overview Quick Sort is a sort of divide-and-conquer algorithm. The algorithm first selects a partitioning element (partition element, sometimes called a pivot), and then rearranges th

Algorithm Graph Search (breadth first, depth first) depth first special important sequencing dynamic programming matching algorithm and network flow algorithm regular expression and string matching Data structure diagram (tree is especially important) map stack/Queue Tries | Dictionary Tree Additional recommended greedy algorithm approximate algorithm of probability method above is the recommendation of Arjun Nayini, the following is Ken George's r

simple; An ordered array can be found using two points; The logarithm of base a of B (probably) is the number of times the B is removed before the result of drizzle 1; The time required for linear lookups is proportional to the number of data items in the array; The time required for binary lookup is proportional to the logarithm of the number of data items in the array; The large O not

of red-Haishi. But they can't all be full, so the height of the 2-3-4 tree is roughly log2 (n+1) and log2 (n+1)/2. Reducing the height of the 2-3-4 tree makes it shorter to find than red-Haishi.On the other hand, each node has more data items to view, which increases the lookup time. Because a linear search is used in a node to view data items, the multiple of the lookup time is proportional to M, which is

when the display, but, The next time the element is inserted, the new element will replace the position of the last element.3) Find optimization--two points to findpublic int find (int value) { int start = 0; int end = Number-1; while (End>start) { int index = (end + start)/2; if (array[index]==value) { return index; } else if (Array[index] >value) { end = index-1; } else { start = in

　　 Packagecom.test.sort.insertion; Public classBinaryinsertsort {/** * @paramargs*/ Public Static voidMain (string[] args) {//TODO auto-generated Method StubSYSTEM.OUT.PRINTLN ("Binary Insert sort sort function implementation")); int[] arr = {23, 54, 6, 2, 65, 34, 2, 67, 7, 9, 43 }; Binaryinsertsort Sort=NewBinaryinsertsort (); System.out.println ("Sort before sequence:"); Sort.printarr (arr); Sort.bininsertsort (arr,0, Arr.length-1); System.out.println ("Sort after sequence:");;

Data structure: The way in which it is arranged in the computer's storage space.Algorithms: Software programs manipulate the data processes of these structures.Data structure Type1. Arrays:Advantages: Fast insertion, direct subscript can be accessed quickly.Cons: Find slow, delete slow, fixed size.2. Ordered arrays:Pros: Faster than no need for array lookups.Cons: Delete and insert slow, fixed size.3. Stack

-operation Traversal, we first recursively use the post-traversal to access the Saozi right subtree, the last access to the root node root node, right subtree, left dial hand tree def postorder (self, Root): "" " recursive implementation of subsequent traversal" " if root = = None: return self.postorder (root.lchild) Self.postorder (root.rchild) print (Root.elem)Breadth-first traversal (hierarchical traversal)From the root of the tree, from top to bottom, from l

Java data structures and algorithms (iii) -- simple sorting Data alone is not enough. Data presentation often needs to be arranged in a certain order. The higher the requirement, the more complicated the sorting. This article only introduces three simple sorting types. 1) B

observers, that is, dependent objects, each time data changes, these 2 view will changeclassHexviewer (object):defUpdate (self, subject):Print 'hexviewer:subject%s has data 0x%x'%(Subject.name, Subject.data)classDecimalviewer (object):defUpdate (self, subject):Print 'decimalviewer:subject%s has data%d'%(Subject.name, Subject.data)if __name__=='__main__': Data1=