题目
Say you have an array for which the ith element is the price of a given stock on day i.
If you were only permitted to complete at most one transaction (i.e., buy one and sell one share of the stock), design an algorithm to find the maximum profit.
Note that you cannot sell a stock before you buy one.
解题思路
遍历价格的同时，记录当前的最低价，如果在当天卖出的最大收益就是当前价格减去最低价
代码
class Solution:
def maxProfit(self, prices: List[int]) -> int:
res, cur_min = 0, float('inf')
for p in prices:
res = max(res, p - cur_min)
cur_min = min(cur_min, p)
return res
