Best Time to Buy and Sell Stock - Leetcode 121 - Python

Best Time to Buy and Sell Stock

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

class Solution:

def maxProfit(self, p: List[int]) -> int:

l, r = 0, 1

mp = 0

while r < len(p):

if p[l] < p[r]:

pro = p[r] - p[l]

mp = max(mp, pro)

else:

l = r

r += 1

return mp

Explaination :

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