Shulou(Shulou.com)06/01 Report--

This article mainly introduces the example analysis of the sorting algorithm in big data, which has a certain reference value. Interested friends can refer to it. I hope you will gain a lot after reading this article.

The basic concept of sorting is to specify records and arrange them in ascending (or decreasing) keyword order.

For example, the final exam scores are sorted in the order of the total score from high to low. This is to rank students' scores from high to low according to the total keyword score. If the final exam results are sorted by the student number, it is sorted by the keyword number.

Stability of sorting

When the keywords of all the records to be sorted are different, the sort result is unique, otherwise the sort result is not unique.

In the file to be sorted, if there are multiple records with the same keywords, and the relative order between the records with the same keywords remains unchanged after sorting, the sorting method is stable; if the relative order between records with the same keywords changes, the sorting method is said to be unstable.

Classification of sorting methods

1. Exchange according to whether data is involved in memory or out of memory.

2. According to the policy, the internal sorting methods can be divided into five categories: insertion sorting, selection sorting, exchange sorting, merging sorting and allocation sorting.

Analysis of sorting algorithm

1. Basic operation of sorting algorithm

(1) compare the size of two keywords

(2) change the pointer to the record or move the record itself.

2. Common storage methods of files to be arranged

(1) using the sequence table as the storage structure

Sorting process: physical movement of records directly.

(2) using linked list as storage structure

Sorting process: no need to move the record, only need to modify the pointer.

(3) store the records to be sorted sequentially, but at the same time create an auxiliary table (such as an index table consisting of keywords and pointers to the location of the record).

Sorting process: you only need to physically rearrange the entries of the auxiliary table. It is suitable for sorting methods that are difficult to implement on linked lists and still need to avoid moving records in the sorting process.

3. Performance evaluation of sorting algorithm

There are two main criteria for evaluating sorting algorithms:

Time complexity and space complexity of the algorithm

Complexity of the algorithm itself

Thank you for reading this article carefully. I hope the article "sample Analysis of sorting algorithms in big data" shared by the editor will be helpful to everyone. At the same time, I also hope that you will support and pay attention to the industry information channel. More related knowledge is waiting for you to learn!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.