You have to start with a clarification, it is that knowing an algorithm of Google completely is nearly impossible, first because they do not reveal the details, and secondly because the algorithm is changed 500 times per year, meaning that constantly change, almost daily, from mild to radical changes and small changes.
What are the algorithms of Google?

Google starts its own definition as follows:
"You want the answer, not billions of web pages.The algorithms are computer programs that look for clues to give back exactly what you want. "

Read more here:- http://www.techbaze.com.ng/2015/11/google-algorithms-to-optimize-seo.html?m=0