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.

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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.


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Constraints:


	1 &lt;= prices.length &lt;= 105
	0 &lt;= prices[i] &lt;= 104


class Solution:
    def maxProfit(self,prices):
        left = 0 #Buy
        right = 1 #Sell
        max_profit = 0
        while right < len(prices):
            currentProfit = prices[right] - prices[left] #our current Profit
            if prices[left] < prices[right]:
                max_profit =max(currentProfit,max_profit)
            else:
                left = right
            right += 1
        return max_profit
class Solution {
    public int maxProfit(int[] prices) {
        int lsf = Integer.MAX_VALUE;
        int op = 0;
        int pist = 0;

        for(int i = 0; i < prices.length; i++){
            if(prices[i] < lsf){
                lsf = prices[i];
            }
            pist = prices[i] - lsf;
            if(op < pist){
                op = pist;
            }
        }
        return op;
    }
}
class Solution {
public:
    int maxProfit(vector<int>& prices) {
        int lsf = INT_MAX;
        int op = 0;
        int pist = 0;

        for(int i = 0; i < prices.size(); i++){
            if(prices[i] < lsf){
                lsf = prices[i];
            }
            pist = prices[i] - lsf;
            if(op < pist){
                op = pist;
            }
        }
        return op;
    }
};
var maxProfit = function(prices) {
    let L = 0;
    let result = 0;
    let length = prices.length;
    for( let R = 1 ;R < length; R++){
        if(prices[L] > prices[R]){
            L = R;
        }else {
                result = Math.max(result, prices[R] - prices[L]);

        }
    }
    return result;
};
Best Time to Buy and Sell Stock