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Leetcode
Easy
Arrays
Greedy
Dynamic Programming
Amazon
Microsoft
Best Time To Buy And Sell Stock
Find the maximum profit from one buy and one sell of a stock over a sequence of daily prices.
Acceptance 82%
Problem Statement
Problem
You are given an array prices where prices[i] is the stock price on day i.
You may complete at most one transaction: buy one share on one day and sell that share on a later day.
Return the maximum profit you can achieve. If no profitable transaction exists, return 0.
Notes
- You must buy before you sell.
- You can only hold one share at a time.
- If prices never rise after a buy day, the best action is to do nothing.
Input Format
- A single integer array
prices. prices[i]represents the stock price on dayi.
Output Format
- Return a single integer: the maximum possible profit from one buy/sell transaction.
Constraints
1 <= prices.length- Prices are non-negative integers.
- You may make at most one buy and one sell.
- The sell day must be strictly after the buy day.
Examples
Sample cases returned by the problem API.
Example 1
Input
prices = [7,1,5,3,6,4]
Output
5
Explanation
Buy on day 2 at price 1 and sell on day 5 at price 6 for a profit of 5.
Example 2
Input
prices = [7,6,4,3,1]
Output
0
Explanation
Prices only decrease, so no profitable transaction exists.
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