What is the specific situation of NBA draft?

The NBA draft is an annual NBA event. In the draft, 30 NBA teams can choose young male players who want to join the NBA. These players usually come from American university-level competitions, but in recent years, more and more international players and high school graduates have been selected. The selected players are called NBA rookies. There are two kinds of NBA rookie selection, namely NBA best rookie selection and NBA all-star rookie selection. Many procedures and rules of NBA draft are still like "seeing flowers in the fog" for some China fans. According to the time division, the annual NBA draft can be roughly divided into two parts. The first part is the draft lottery: the NBA began to implement the draft lottery from 1985. Every year when the playoffs are in full swing, the NBA will convene teams that fail to enter the playoffs to hold a lottery ceremony to determine the ownership of the top three draft picks in the future. In the lucky draw ceremony, the host will take out 1- 14 ping-pong balls and put them into the container. Four balls are randomly selected from 14 balls, regardless of numerical order. A * * can produce 100 1 possible combinations. Before the draw, the teams that didn't qualify for the playoffs had been ranked in reverse order according to the regular season record, and the corresponding combination number (probability) of winning the first prize was obtained. For example, in the 2004-05 season, 14 team did not enter the playoffs. In this 14 team, the eagle with the worst record got 250 combinations, that is, there was a 25% chance to win the first place, and the Hornets with the second worst record got 199, that is, 19.9% chance. After the draw for No.1 draft, four table tennis balls were put back into the container, and the ownership of No.2 and No.3 draft picks was decided again. After that, the remaining No.4-30 draft picks in the first and second rounds were decided in reverse order according to the results of the regular season.