309. 买卖股票的最佳时机含冷冻期

class Solution {
    public int maxProfit(int[] prices) {
        if(prices == null || prices.length <= 1)return 0;
        // dp[i][0]:第i天持有股票的利润
        // dp[i][1]:第i天持有现金的利润
        int[][] dp = new int[prices.length][2];

        dp[0][0] = -prices[0];
        dp[0][1] = 0;
        dp[1][0] = Math.max(dp[0][0], -prices[1]);
        dp[1][1] = Math.max(dp[0][1], dp[0][0] + prices[1]);

        for(int i = 2; i < prices.length; i++){
            dp[i][0] = Math.max(dp[i - 1][0], dp[i - 2][1] - prices[i]);
            dp[i][1] = Math.max(dp[i - 1][1], dp[i - 1][0] + prices[i]);
        }

        return dp[prices.length - 1][1];
    }
}

714. 买卖股票的最佳时机含手续费

class Solution {
    public int maxProfit(int[] prices, int fee) {
        int[][] dp = new int[prices.length][2];

        dp[0][0] = -prices[0] - fee;
        dp[0][1] = 0;

        for(int i = 1; i < prices.length; i++){
            dp[i][0] = Math.max(dp[i - 1][0], dp[i - 1][1] - prices[i] - fee);
            dp[i][1] = Math.max(dp[i - 1][1], dp[i - 1][0] + prices[i]);
        }

        return dp[prices.length - 1][1];
    }
}