How to realize lottery algorithm

First of all, the user table of your database needs to store the id of the applicant, whether to participate in the first lottery (first_row), whether to participate in the first lottery (second), whether to win the second lottery (second_row) and the basic information of the applicant (name, password ...).

Then register (while registering, the first one = 1 and the second one =0). At the end of the first registration time, if the number of applicants for the first time exceeds 50, lots will be drawn by first_row= 1.

Then register for the second time. Those who did not win the first lottery (second_row==0) can choose whether to register (second= 1) when logging in. At the end of the second registration time, all users with seconds == 1 draw lots, and the winner with seconds _ line = 1.