Best Time to Buy and Sell Stock

Easy

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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 <= 10^5
•0 <= prices[i] <= 10^4

Show Hints (3)

Hint 1: Think of this as finding the maximum difference where the larger element comes after the smaller one.

Hint 2: Track the minimum price seen so far as you iterate.

Hint 3: At each position, calculate profit if you sold today (current price - min price so far).

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Test Results

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