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Merge sort 🎈🎆🎇 preface: 1, Priority queue heap PriorityQueue 2, Deep understanding of fast scheduling and optimization The number of times that merge sort is often tested in the eight sorts can be said to be among the best, and its status is also very high, which can not be ignored. In the sort of quick sort, merge sort and heap s ...

Dutch National Flag Problem         a. Given a sequence arr and a number num, put > num on the right of the array and < = num on the left of the array         b. Given a sequence arr and a number num, put > num on the right of the array, < num on the left of the array, and equal in the midd ...

(recently, I was studying the book introduction to algorithms. Before, I liked to write notes by hand, but then I found that I always lost my notes, so I planned to make an electronic version of notes)   (in addition, pseudo code is used in the book, and python code is used in the notes if you need to try.) 2.1 insert sort     &nb ...

subject Problem solving ideas Firstly, the idea of two-dimensional to one-dimensional is discussed. Convert each point to abscissa multiplied by N + ordinate. It seems that it can be realized, but this problem needs four points, so 3 and 4 are implicitly connected. So it will be Wa. When we first increase N by 1, each available XY will not ...

Bubble sorting Start from the first element of the sequence to be sorted, constantly compare the values of adjacent elements, exchange if it is found that the reverse order, and gradually move the elements with larger values from front to back. Every time the maximum value of the sequence to be sorted is found, the maximum value is fi ...

160 intersecting linked list Given two linked lists, judge whether they intersect at a point, and find the intersection node. The input is two linked lists and the output is one node. If there are no intersecting nodes, an empty node is returned. Input: intersectVal = 8, listA = [4,1,8,4,5], listB = [5,0,1,8,4,5], skipA = 2, skipB = 3 Out ...

Chapter III Search and Graph Theory 1. Depth-first search (dfs) Search down from start to finish, find the bottom and backtrace down to finish, use stack to store data, have two concepts of backtrace and pruning, do not have the shortest Array Array (Violent Search, Full Array) To restore the state to its original state after backtracking ...

Array overviewArray declaration creationArray usageMultidimensional arrayArrays classSparse array Definition of array An array is an ordered collection of data of the same typeArray describes several data of the same type, which are arranged and combined in a certain orderEach data is called an array unit, and each array element can access ...

LeetCode problem brushing - algorithm learning plan (Introduction) Title Description Introduction of ideas If the linked list is bidirectional, reversing the linked list is very simple. You only need to exchange the forward pointer and backward pointer. But now the topic specifies a single linked list, how to reverse it? In fact ...

When adding objects using HashSet in Java programming, the equals method and hashCode method must be rewritten because they must comply with the characteristics of Set (no order and no repetition). First: The Set set has no order and cannot be repeated. Why: simulate a collection of reality. The repetition here is only the repetition of the ...