robert lafore data structures and algorithms in java

-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

Basic Concepts I. Data and structure Data: All of the objects that can be entered into a computer and can be processed by a computer are collectively referred to as a specific symbolic representation of the information processed by the computer. Data elements: An "individual" in the data, the basic unit discussed in t

What is a data structure: Statistics + relationshipsRelationships can be divided into: sets, linear structures, tree structures, graph structures or network structures.Storage structure: Sequential storage, chained storage, index storage, hash storage.Data type: Atomic type, struct type1. Time complexity of the algorit

smaller than their own elements can stop the comparison, because the left is already an orderly state, find smaller than their own elements, there is no further comparison.　　 ? The number of rounds to be inserted is the same as the bubbling sort, but I start with 1 because we assume that the first element is already in an orderly state.? The inner loop starts from the current position, compares it to the previous element, and if it finds a smaller element than itself, stops the comparison

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

| | j>1)//If to the end, return prompt{return ERROR;}S= (linklist) malloc (sizeof (Node));S->data =e;//Value AssignmentThe following two sentences can not be written anti-ohS->next = p->next;P->next = s;return OK;}Single-linked list delete operationDelete the A2 in the single-linked list a1,a2,a3650) this.width=650; "Width=" 518 "height=" 242 "title=" 11.jpg "style=" width:342px;height:143px; "src="/HTTP/ S3.51cto.com/wyfs02/m00/57/13/wkiol1sq75iic-u

algorithm is executed on different computers, and the execution time is not the same.Therefore, the operational efficiency should be related to the execution steps, which will be the time complexity of the execution steps.In the first algorithm: T (n) = n^3 * 2In the second algorithm: T (n) = n^2 * 3If the system and bias items are not considered, then the progressive function, using the progressive function representation, is the large O notation:In the first algorithm: T (n) = O (n^3)In the s

is more complex because: Need to handle different node types, very cumbersome A multiple comparison operation is required to move the node down Need to move up to split the 4-node node There are a number of scenarios for splitting 4-node nodes 2-3 Find trees are more complex to implement, and in some cases the balancing operation after insertion may result in reduced efficiency. The improved red-black tree based on the 2-3 find tree is not only more efficient, but also

algorithm is O (NLOGN).2: Worst of all, that's what I'm talking about. The maximum and minimum values are selected:Then look at the worst-case fast-track, when the sequence to be sorted is in a positive or reverse order, and each partition has only one sub-sequence that is less than the last one, noting that the other is empty. If the recursive tree is drawn, it is a diagonal tree. You need to perform a n‐1 recursive call at this time, and the first Division I need to go through the N‐i keyword

;//I fall back to the next last match firstj =0;//J fallback to the first of the substring } if(J = =searchstr.length) {returnIJ; } }}I is the subscript positioning of the main string, and J is the subscript location of the substring.When the main string string is equal, it enters the loop mode of the substring, and when the number of cycles J satisfies the substring length, the validation is exactly the same.When the main string string is not equal, it is necessary to move the

their definitions into a hash list; The second part lets the user enter a word, and the program gives the definition of the word.// 字典类function Dict () { this.hashTable = new HashTable(); this.save = save; this.find = find;}function save (word, description) { this.hashTable.put(word, description);}function find (word) { return this.hashTable.get(word);}// 示例let d = new Dict();d.save('Mazey', 'a strong man.');d.save('Cherrie', 'a beautiful girl.');d.save('John', 'unknown.');consol