In this note，you will not find the concept of QS and the method of how to compute the cost of time and space of this algorithm。This page will not refer to them
at all。However，i will arouse your awareness of main traits of this algorithm to assist you with your deeper understanding of thie algorithm and hope after this,you will always be able to write the correct code of implementation of this piece.
Let us take a quick walkthrough of this algorithm GIF,so that i will remind you of the algorithm.
and take a look of this code wriiten by me,and i will compare mine to others,then you will know what i say.