题解 | #买卖股票的最好时机(二)#

class Solution {
  public:
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     * 计算最大收益
     * @param prices int整型vector 股票每一天的价格
     * @return int整型
     */
    int maxProfit(vector<int>& prices) {
        vector<int> dp(prices.size() + 1, 0);
        int minN = 1E4 + 1;
        int maxN = minN;
        for (int i = 1; i <= prices.size(); i++) {
            if (maxN < prices[i - 1]) {
                minN = maxN;
                maxN = prices[i - 1];
            } else {
                minN = prices[i - 1];
                maxN = minN;
            }
            dp[i] =  dp[i - 1] + maxN - minN;
        }
        return dp[prices.size()];
    }
};