Java Lookup Algorithm (three): Inverted index

[What is inverted index]

Index: Just like the catalogue of books, we can quickly find the corresponding chapters through the catalogue.

The inverted index stems from the fact that the actual application needs to find records based on the value of the attribute, for example, by finding the corresponding article through the words in the article.

[Inverted Index example]

Suppose there are three articles, the contents of which are:

Article 1:it is what it is

Article 2:what is it

Article 3:it is a banana

We can get the following inverted index table:

Key words	Your article
A	{2}
Banana	{2}
Is	{0, 1, 2}
It	{0, 1, 2}
What	{0, 1}

after establishing the index table above, if you find the keyword "banana", we can quickly know it in article 2.

Java Lookup Algorithm (three): Inverted index