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Depth first search application Example 1: alphabetical arrangement (subject library 2698) Given a string composed of different lowercase letters, output all the full permutations of the string. Let's assume 'a' < 'B' <... < 'for lowercase letters Y '<' Z ', and the letters in the given string have been arranged from small to large ...

1. Fast power algorithm template Find mk%p, time complexity O(logk). int qmi(int m, int k, int p) { int res = 1 % p, t = m; while (k) { if (k&1) res = res * t % p; t = t * t % p; k >>= 1; } return res; }   2. Binary search algorithm template There are two bisection templates, which are ...

Introduction to JAVA array (I) So far, the basic syntax of java has been basically summarized. The next thing to learn is array. 1. Overview of Array Array is a collection of multiple data of the same type arranged in a certain order, named with a name, and managed uniformly by numbering.Common concepts of arrays: 1. Array name 2. Elements 3 ...

1. Basic Theory When processing feature descriptors suitable for multiple images, there are two main feature detection methods, one is angle-based detection, the other is to process all areas in the image. Here we will focus on angle-based detection. In 1988, Harris and Stephens presented an angle detection algorithm, HS Angle Detector. See p ...

preface Blue Bridge Cup 2021 provincial competition, programming problem (C + +) 1, Title Description Xiaolan wants to cooperate with her friends to develop a time display website. On the server, the friend has obtained the current time, which is expressed as an integer. The value is the number of milliseconds from 00:00:00 on Janua ...

Ordered table Function: supports all operations of hash table. Keys are organized in order (hash table is out of order)Time complexity: all operations are O(log N) levelImplementation method: (1) Red black tree (2)AVL (3)SBT (4) Skip list (1) , (2), (3) all attribute BST (balanced search binary tree) Search Binary Tree There are general ...

Before introducing the principle of interface isolation, let's take a look at the first example in the following example - counterexample 1, Examples 1. Counterexample (1) Class diagram description Because the class diagram is relatively clear, let's look at the class diagram first As you can see, DogPlays Java and CatPlays Java impl ...

Backtracking algorithm is actually a similar exhaustive search attempt process, which is mainly to find the order of the problem in the search attempt process. When it is found that the solution conditions are not met, it will "backtrack" (i.e. backtrack) and try other paths. Therefore, backtracking method is known as "common pro ...

Some codes involve the knowledge mentioned before Quick sort Two way fast platoon Improve according to the one-way fast sorting in the previous section. In order to prevent each cycle, the same number is on one side, such as: 3 4 1 2 3 2 1 3 1 3 5 4 Single way fast platoon: 1 1 2 1 3 3 3 4 5 4 In this way, the case equal to thre ...

Say something before brushing If you want to cut the length of the article, you will say it in addition to the length of the code, Because too much time is wasted in writing articles! In fact, it's not difficult to brush the questions. What's difficult is to insist! This column is the classic title of sword finger offer, And record you ...