# Best Time to Buy and Sell Stock – Leetcode Solution

In this post, we are going to solve the 121. Best Time to Buy and Sell Stock problem of Leetcode. This problem 121. Best Time to Buy and Sell Stock is a Leetcode easy level problem. Let’s see code, 121. Best Time to Buy and Sell Stock – Leetcode Solution.

## Problem

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

You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock.

Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return `0.`

### Example 1 :

``````
Input: prices = [7,1,5,3,6,4]
Output: 5
Explanation: Buy on day 2 (price = 1) and sell on day 5 (price = 6), profit = 6-1 = 5.
Note that buying on day 2 and selling on day 1 is not allowed because you must buy before you sell.
``````

### Example 2 :

``````
Input: prices = [7,6,4,3,1]
Output: 0
Explanation: In this case, no transactions are done and the max profit = 0.
``````

### Constraints

• `1 <= prices.length <= 105`
• `0 <= prices[i] <= 104`

Now, let’s see the code of 121. Best Time to Buy and Sell Stock – Leetcode Solution.

# Best Time to Buy and Sell Stock – Leetcode Solution

### 121. Best Time to Buy and Sell Stock – Solution in Java

```class Solution {
public int maxProfit(int[] prices) {
int profit = 0;
for(int i=1; i< prices.length; i++){
}
return profit;
}
}```

### 121. Best Time to Buy and Sell Stock – Solution in C++

```class Solution {
public:
int maxProfit(vector<int>& prices) {
int profit = 0;
for(int i=1; i< prices.size(); i++){
}
return profit;
}
};```

### 121. Best Time to Buy and Sell Stock– Solution in Python

```class Solution:
def maxProfit(self,prices):