188. Best Time to Buy and Sell Stock IV

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 at most k transactions.
Note:
You may not engage in multiple transactions at the same time (ie, you must sell the stock before you buy again).
Example 1:
Input: [2,4,1], k = 2
Output: 2
Explanation: Buy on day 1 (price = 2) and sell on day 2 (price = 4), profit = 4-2 = 2.
Example 2:
Input: [3,2,6,5,0,3], k = 2
Output: 7
Explanation: Buy on day 2 (price = 2) and sell on day 3 (price = 6), profit = 6-2 = 4.
             Then buy on day 5 (price = 0) and sell on day 6 (price = 3), profit = 3-0 = 3.

 

class Solution {
    public int maxProfit(int k, int[] prices) {
        int n = prices.length;
        if(n <= 1) return 0;
        
        if(k >= n / 2){
            int maxPro = 0;
            for(int i = 1; i < n; i++){
                if(prices[i] > prices[i - 1]){
                    maxPro += prices[i] - prices[i - 1];
                }
            }
            return maxPro;
        }
        
        int[][] dp = new int[k + 1][n];
        for(int i = 1; i <= k; i++){
            for(int j = 1; j < n; j++){
                dp[i][j] = dp[i][j - 1];
                for(int m = 0; m < j; m++){
                    dp[i][j] = Math.max(dp[i][j], prices[j] - prices[m] + dp[i - 1][m]);
                }
            }
        }
        return dp[k][n - 1];
        
    
        
    }
}

 https://leetcode.com/problems/best-time-to-buy-and-sell-stock-iv/discuss/54113/A-Concise-DP-Solution-in-Java