How does php compare two paragraphs?

How can I compare two texts? It is how to give two paragraphs of text, and mark the modification process like the correction process after dictation to compare the two strings (paragraphs) insert, modify (based on characters), delete. Github example...

How can I compare two texts?

It is how to give two paragraphs of text, and mark the modification process like the correction process after dictation to compare the two strings (paragraphs) insert, modify (based on characters), delete. The github example is very good, but it does not seem to be a minimal edit, rather than a word-by-word operation.

For example:

1st sentence: Why I Cann't changed it. Becuase we can't.

2nd sentence: Why we can't change it now? Because you can.

The program can compare the two sentences, find the differences, automatically skip the same part, and mark different places.

How does php implement this algorithm? A score is also given. Is it related to the editing distance? Keyword: php diff? Or compare strings?

Take Hujiang as an example: http://ting.hujiang.com/mansu...

I think https://github.com/kijtra/tex...this algorithm is not as useful as Shanghai: