【DP + 卖股票】LeetCode 309. Best Time to Buy and Sell Stock with Cooldown

LeetCode 309. Best Time to Buy and Sell Stock with Cooldown

Solution1:
比较有难度的一道动态规划题了！
参考网址：http://zxi.mytechroad.com/blog/dynamic-programming/leetcode-309-best-time-to-buy-and-sell-stock-with-cooldown/

每一天都对应着一个动作，buy,sell和rest。相当于维护三个数组。。

class Solution {
public:
    int maxProfit(vector<int>& prices) {
        int sold = 0;
        int rest = 0;
        int hold = INT_MIN;
        for (const int price : prices) {
            int prev_sold = sold;
            sold = hold + price;
            hold = max(hold, rest - price);
            rest = max(rest, prev_sold);
        }
        return max(rest, sold);
    }
};