leetcode 122. Best Time to Buy and Sell Stock II

python leetcode 

122. Best Time to Buy and Sell Stock II

Say you have an array for which the ith element is the price of a given stock on day i.

Design an algorithm to find the maximum profit. You may complete as many transactions as you like (ie, buy one and sell one share of the stock multiple times). However, you may not engage in multiple transactions at the same time (ie, you must sell the stock before you buy again).

#coding=utf-8

class Solution(object):

    def maxProfit(self, prices):

        """

        :type prices: List[int]

        :rtype: int

        """

        #一天可以将股票进行多次买卖，但必须先买后卖

        #正是因为一天可以多次买卖，所以可以从局部最优考虑这个问题

        sum=0

        for i in range(len(prices)-1):

            if prices[i+1]>prices[i]:

                sum=sum+prices[i+1]-prices[i]

        return sum

S=Solution()

print S.maxProfit([2,3,1,5,6,9,2])