# Best Time to Buy and Sell Stock II

## Question

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).

Example
Given an example [2,1,2,0,1], return 2


## 题解

### Python

class Solution:
"""
@param prices: Given an integer array
@return: Maximum profit
"""
def maxProfit(self, prices):
if prices is None or len(prices) <= 1:
return 0

profit = 0
for i in xrange(1, len(prices)):
diff = prices[i] - prices[i - 1]
if diff > 0:
profit += diff

return profit


### C++

class Solution {
public:
/**
* @param prices: Given an integer array
* @return: Maximum profit
*/
int maxProfit(vector<int> &prices) {
if (prices.size() <= 1) return 0;

int profit = 0;
for (int i = 1; i < prices.size(); ++i) {
int diff = prices[i] - prices[i - 1];
if (diff > 0) profit += diff;
}

return profit;
}
};


### Java

class Solution {
/**
* @param prices: Given an integer array
* @return: Maximum profit
*/
public int maxProfit(int[] prices) {
if (prices == null || prices.length <= 1) return 0;

int profit = 0;
for (int i = 1; i < prices.length; i++) {
int diff = prices[i] - prices[i - 1];
if (diff > 0) profit += diff;
}

return profit;
}
};


## Reference

• soulmachine 的卖股票系列