Implement a simple stock price display systemwhich will show High, Low and Last price for a given stock throughout one day.The data comes from a real-time feed and have the following messages: PriceUpdate(t, P) -> Price of Stock A at timet is P. Correction(t, NewP) -> Price of Stock A attime t is rectified to NewP Remove(t) -> Disregard the price feedreceived at time t. PriceUpdate(10100,850.50) -> high = 850.50, Low = 850.50, Last = 850.50 PriceUpdate(10200,852.25) -> high = 852.25, Low = 850.50, Last = 852.25 PriceUpdate(10300,848.00) -> high = 852.25, Low = 848.00, Last = 848.00 Correction(10200, 849.00) -> high = 850.50, Low = 848.00, Last 848.00 PriceUpdate(10400,855.00) -> high = 855.00, Low = 848.00, Last = 855.00 Correction(10300, 853.00) -> high = 855.00, Low = 850.50, Last = 855.00 PriceUpdate(10500,854.00) -> high = 855.00, Low = 848.00, Last = 854.00 Correction(10500,853.25) -> high = 855.00, Low = 848.00, Last = 853.25 Remove(10300) -> high = 855.00, Low = 849.00, Last = 853.25 简单说来PriceUpdate就是添加新的（timestamp, price）, Correction是改之前的(timestamp, price), 求实现当前high(), low(), last()
G面经： Design Stock Price Display System
原文：http://www.cnblogs.com/EdwardLiu/p/6369029.html