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Topic source 149. Maximum number of points on a line Title details Give you an array of points, where points[i] = [xi, yi] represents a point on the X-Y plane. Find the maximum number of points on the same line. Example 1: Input: points = [[1,1],[2,2],[3,3]] Output: 3 Example 2: Input: points = [[1,1],[3,2],[5,3],[4,1],[2,3],[1,4]] Output: 4 ...

Symbol table Symbol table is set and map. In c + +, there are map and set based on red black tree and unordered based on hash function_ map，unordered_set. The symbol table used in this code is my own implementation, according to the implementation method of algorithm 4. Blacklist The blacklist is to filter out what is on the list and ...

jdk1.7 -: it is composed of array + linked list. The array is the main body. The linked list mainly exists to solve hash conflicts (i.e. the array index values calculated through the key are the same) (the "zipper method" solves conflicts). jdk1.8 +: it is composed of array + linked list + red black tree. There are great changes in r ...

   students, today we will deeply analyze the source code of HashMap. I believe many students will be asked about the source code during the interview. Which one is the most asked? Most students will definitely think of HashMap. Through the study of this article, you will be able to easily master the source code knowledge of HashMa ...

The most elegant way to write a value in a Map that increases or decreases automatically or re operates a value without calling get() and put() I believe you can always meet such needs in the process of development: query a key value in the Map, add one if there is one, and put the new key value as 1 if there is no one (or perform other operat ...

preface As for thread safety, the put method can expose the problem of thread safety. When two different hashcode s get the same index through hash calculation, they should form a linked list. However, if multiple threads are placed in the same index, it may be overwritten, which is when judging whether the table[index] is empty. No more nons ...

Before reading this article, it is recommended to read the blogger's article on HashMap: HashMap source code analysis + interview questions HashSet source code analysis 1, Basic introduction The underlying implementation is based on HashMap, so it is not guaranteed to iterate according to the insertion order or other order The time-con ...

summary HashMap allows null keys and values. Hashtable does not allow null values or null keys. NullPointerException will be thrown. The time complexity of get put is constant. HashMap has two parameters that affect its performance: initial capacity, initial capacity and load factor. Capacity refers to the number of bucket s, that is, the l ...

Learning points of Java and big data development (under continuous update...) Reference from HashMap? ConcurrentHashMap? I believe no one can stop you after reading this article! 1, Foreword Key and value such as Map are very classic structures in software development. They are often used to store data in memory. This article mainl ...

1, Foreword Write in front: it took a day to sort out the data collected by small codewords. It's helpful for you. One key three times in a row. Ha, thank you!! HashMap is often encountered in our daily development. The source code and underlying principle of HashMap must be asked in the interview. Therefore, we should master it, which is ...