If you fill in a purchase order of 59000, you will reach a deal with 58000; Fill in 57000 to sell, and it's also 58000 to sell.

If you fill in 59,000 to sell and 57,000 to buy, you won't make a deal.

Standard: Pay the bill at the same time, and the highest price will be sold first; Pay the same price, and the first person to place an order will make a deal first; And vice versa, sell the order at the same time, and the lowest price will be the first transaction; If the orders are sold at the same price, the first order will be executed first.

If someone is ahead of you and you want to make a deal first, then you want to buy first, the price is higher than that of the person ahead of you, and you want to sell first, and the price is lower than that of the person ahead of you.