In this post, we are going to solve the 309. Best Time to Buy and Sell Stock with Cooldown problem of Leetcode. This problem 309. Best Time to Buy and Sell Stock with Cooldown is a Leetcode medium level problem. Let’s see code, 309. Best Time to Buy and Sell Stock with Cooldown – Leetcode Solution.

Problem

You are given an array prices where prices[i] is the price of a given stock on the ith day.

Find the maximum profit you can achieve. You may complete as many transactions as you like (i.e., buy one and sell one share of the stock multiple times) with the following restrictions:

• After you sell your stock, you cannot buy stock on the next day (i.e., cooldown one day).

Note: You may not engage in multiple transactions simultaneously (i.e., you must sell the stock before you buy again).

Example 1 :

Input: prices = [1,2,3,0,2]
Output: 3
Explanation: transactions = [buy, sell, cooldown, buy, sell]

Example 2 :

Input: prices = [1]
Output: 0

Constraints

• 1 <= prices.length <= 5000
• 0 <= prices[i] <= 1000

Now, let’s see the code of 309. Best Time to Buy and Sell Stock with Cooldown – Leetcode Solution.

Best Time to Buy and Sell Stock with Cooldown – Leetcode Solution

309. Best Time to Buy and Sell Stock with Cooldown – Solution in Java

class Solution {
    public int maxProfit(int[] prices) {
        
        int obsp = -prices[0];
        int ossp = 0;
        int ocsp = 0;
        
        for(int i=1;i<prices.length;i++){
            
            int nbsp = 0;
            int nssp = 0;
            int ncsp = 0;
            
            if(ocsp - prices[i] > obsp){
                nbsp = ocsp - prices[i];
            }else{
                nbsp = obsp;
            }
            
            if(obsp + prices[i] > ossp){
                nssp = obsp + prices[i];
            }else{
                nssp = ossp;
            }
            
            if(ossp > ocsp){
                ncsp = ossp;
            }else{
                ncsp = ocsp;
            }
            
            obsp = nbsp;
            ossp = nssp;
            ocsp = ncsp;
            
        }
        return Math.max(obsp,Math.max(ossp,ocsp));
    }
}

309. Best Time to Buy and Sell Stock with Cooldown – Solution in C++

class Solution {
public:
    int maxProfit(vector<int>& prices) {
        int obsp = -prices[0];
        int ossp = 0;
        int ocsp = 0;
        
        for(int i=1;i<prices.size();i++){
            
            int nbsp = 0;
            int nssp = 0;
            int ncsp = 0;
            
            if(ocsp - prices[i] > obsp){
                nbsp = ocsp - prices[i];
            }else{
                nbsp = obsp;
            }
            
            if(obsp + prices[i] > ossp){
                nssp = obsp + prices[i];
            }else{
                nssp = ossp;
            }
            
            if(ossp > ocsp){
                ncsp = ossp;
            }else{
                ncsp = ocsp;
            }
            
            obsp = nbsp;
            ossp = nssp;
            ocsp = ncsp;
            
        }
        return max(obsp,max(ossp,ocsp));
    }
};

309. Best Time to Buy and Sell Stock with Cooldown – Solution in Python

class Solution:
    def maxProfit(self, prices: List[int]) -> int:
        if len(prices)==1:
            return 0
        dpb0=-prices[0]
        dps0=0
        dpb1=-min(prices[0],prices[1])
        dps1=max(dps0,dpb0+prices[1])
        for i in range(2,len(prices)):
            temp=max(dpb1,dps0-prices[i])
            temp2=max(dps1,dpb1+prices[i])
            dpb0=dpb1
            dps0=dps1
            dpb1=temp
            dps1=temp2
        return dps1 if dps1>0 else 0

Note: This problem 309. Best Time to Buy and Sell Stock with Cooldown is generated by Leetcode but the solution is provided by CodingBroz. This tutorial is only for Educational and Learning purpose.