Alan's vegetable stall is simple but modern in concept. He has adopted a self-service scheme where customers can choose what they want to buy and pay at the cashier.As soon as he arrived, Alan was busy checking his inventory. Some of the vegetables were wilted and even rotten, and had to be thrown away immediately because they were no longer edible.Meanwhile, more durable vegetables such as potatoes, eggplants, carrots and cabbage were in short supply. This meant that Alan had to go shopping again to replenish the stock.“Ah, I still can't start selling today. I have to go shopping first,” muttered Alan after he finished checking all the supplies.Just as Alan was about to check the cash register, the glass door of the stall opened. A young woman wearing an elegant blazer appeared with a smile.A fragrant aroma filled the shop as soon as she entered. It was the typical scent of expensive perfume worn by the rich.“Sorry, our shop is still closed today. Please come back tomorrow,” Ala