data structures and algorithms in java online tutorial

True Second, collections. Ordereddict: Dictionary with OrderOrdereddict internally maintains a doubly linked list to record the order in which key values are inserted, update the key value does not affect the original order, insert key value is inserted at the end, so its memory consumption is twice times the normal dictionary ,From collections Import ORDEREDDICTD = Ordereddict () d[' a '] = 1d[' c '] = 3d[' b '] = 2print (d, D.items ()) Ordereddict (' A ', 1), (' C ', 3)

-set receives a tree height effect and is less efficient. Therefore, there are two kinds of improved heuristic algorithms.The first is to merge by rank, and for each node to record his height, change the father of the smaller node to the larger one. If both sides are equal, select one as the father, and the rank of the root node plus one.The second is path compression, and each time the find-set is called, the father of the node found on the path is changed directly to the root node.1make-SET (x

1. The principle of hill sorting2. Code implementationdefShell_sort (alist): N=Len (alist)#Initial StepGap = N/2 whileGap >0:#Insert Sort by step forIinchRange (Gap, N): J=I#Insert Sort whileJ>=gap andALIST[J-GAP] >Alist[j]: alist[j-GAP], alist[j] = alist[j], alist[j-Gap] J-=Gap#get a new step sizeGap = GAP/2alist= [54,26,93,17,77,31,44,55,20]shell_sort (alist)Print(alist)Attention:(1) Hill sort uses the idea of splitting up and merging, splitting apart3. Complexity of TimeOp

node is now Point to the head of the now node's next pointer; Set the now node to the head of the new rollover completion node header now; Point to head now, and so on, the next pointer to the previous node of the now node. 3. Two points search common scenes Finding a number in an ordered sequence; For example, given an array of arr, determine if the integer m is in arr (Train of thought: Determine the size of the mid-to-m re

The implementation of the dictionary// 字典类function Dictionary () { this.add = add; this.dataStore = new Array(); this.find = find; this.remove = remove; this.showAll = showAll; this.count = count; this.clear = clear;}function add (key, value) { this.dataStore[key] = value;}function find (key) { return this.dataStore[key];}function remove (key) { delete this.dataStore[key];}function showAll () { let datakeys = Array.prototype.slice.call(Object.keys(this.dataStore)

node1.next = node3; node3.previous = node1; node3.next = node2; node2.previous = node3; node2.next = node4; node4.previous = node2; }};DList.prototype.advance = function (n, item) { let currNode = this.find(item); while (n--) { this.goPrevious(currNode); }};// 示例let names = new DList();names.insert('Mazey', 'head');names.insert('Cherrie', 'Mazey');names.insert('John', 'Cherrie');names.insert('Luna', 'John');names.insert('Ada', 'Luna'

efficiency: In a merge sort, the maximum value of this secondary storage space is not more than N, so the spatial complexity of the merge algorithm is θ (n) in order to combine the sub-sequences to use additional storage space.Time efficiency: The merging algorithm is a typical divide-and-conquer algorithm with a time complexity of 0 (n log n).　3. Algorithm examplesMergesort.javaPackage Com.test.sort.merge;public class MergeSort {/** * @param args */public static void main (string[] args) {//TO

" definition of algorithmic time complexity"At the time of the algorithm analysis, the total number of executions of the statement T (N) is a function of the problem size n, which then analyzes the change of T (n) with N and determines the order of magnitude of T (N). The time complexity of the algorithm, which is the time measurement of the algorithm, is recorded as: T (n) = O (f (n)). It indicates that with the increase of the problem size n, the growth rate of the algorithm execution time is

Bucket sortBarrel sequencing has been used since the 1956, and the basic idea of the algorithm is proposed by E.J.ISSAC and R.c.singleton.This algorithm is like having 11 barrels, numbered from 0~10. Each occurrence of a number, in the corresponding number of buckets put aA little flag, and then just count the few small flags in each bucket OK. For example, there are 1 small flags in bucket 2nd, indicating2 appeared once, and in the 3rd barrels there were 1 small flags, indicating that 3 appeare

and J to point to the leftmost and rightmost of the sequence, respectively. At first, the variable I points to the leftmost part of the sequence, which is the number 6, and J points to the far right of the sequence, pointing to the number 8, as shown inFirst J moves from right to left, so long as it finds a number smaller than 6, it stops, and J is in the 5 position. I then start from left to right, as long as I find a number greater than 6 to stop, so it to the position of 7This is where the t

Using system;using system.collections.generic;using system.linq;using system.text;using System.Threading.Tasks; Namespace selectsort{class Program {static void Main (string[] args) {int[] Arry = {1, 4, 5,6,2,9,0,8,3,10}; Selectesort (Arry, Arry. Length); for (int i = 0; i Because of the two for loops, the time complexity is O (n^2), which is a simple but very slow sort.Selection and sequencing of algorithms and

!) "; return; } $elem = $this->stack[$this->top]; unset ($this->stack[$this->top]); $this->top--; return $elem; }//Print stack public function show () {for ($i = $this->top; $i >=0; $i-) {echo $this->stack[$i]. " "; } echo ""; }} $stack = new stack (); $stack->push (3); $stack->push (5); $stack->push (8); $stack->push (7); $stack Push (9); $stack->push (2); $stack->show (); $stack->pop (); $stack->pop (); $stack->pop (); $stack Show (); Copyright

1. The main reference documents: Introduction to AlgorithmsThe foundation of algorithmic design Shen Xiaojun"C + + data Structures""Algorithmic Python"Timus All algorithmic code implementations for this series of posts are python. On the basis of this, some topics will add additional C + +, java. 2. Already finished meat (real-time update) Advanced algorithm Di

or tools including, but not limited to, the following ranges:C/c++/c# WriteJava Write generationIt generationPython writesTutoring Programming JobsThe MATLAB Generation writesHaskell writesProcessing WriteLinux Environment SetupRust Generation WriteData Structure assginment Data structure generationMIPS Generation WritingMachine Learning Job WritingOracle/sql/postgresql/pig database Generation/Generation/CoachingWeb development, Web development, Web

In general, the data structures on textbooks include arrays, single-linked lists, stacks, trees, and graphs. The data structure I'm referring to here is a question of how to represent an object, and sometimes a single variable declaration can be overwhelming, such as a int,string,double or even a one-dimensional array, a two-dimensional array that cannot fully ex

What is a data structure :The data structure is the way that the computer stores and organizes it.A data structure is a collection of elements that have one or more specific relationships to each othertypically, a well-chosen data structure can lead to higher operational or storage Efficiency.

tree, or red-black tree.1. RelationshipTreeSet uses treemap in the adorner mode, they both implement the same interface Navigablemap, and in TreeSet, they hold the navigablemap reference, in fact the TreeSet will be treemap when it is constructed.public class TreesetThen look at the list structure in the TREEMAP definition, Entry, which left and right respectively for the child and the child.Static Final class Entry2. The sort implementation sort is only for key (set is only using the key of th

Doing the project today, the whim, decided to use their usual Java data type collation (Java Master and the basic good netizen don't look down, kneeling beg not to spray), are very basic very simple things, but I think it is necessary, good memory than bad pen, oneself in order to facilitate the development of it, Java

Details of data structures in JavaThis article describes the data structure in Java, and this article attempts to explain to the reader the role of each class and how to use it correctly through a simple description. Come and see this article together! Perhaps you have mastered the use of

, and clear methods for that collection). But if the iterator calls its own remove method, it is still legal.3.List interfaceThe Java.util package inherits the collection interface. Here are just a few important methods. Public Interface extends Collection{ AnyType get (int idx); AnyType Set (int idx, AnyType newval); void Add (int idx, AnyType x); void Remove (int idx); Listiteratorint poss);}View CodeIndex 0 is in the front segment of the table, size ()-1 represents t