You're a buyer/seller and your business is at stake. You need to make profit... Or at least, you need to lose the least amount of money! Knowing a list of prices for buy/sell operations, you need to pick two of them. Buy/sell market is evolving across time and the list represent this evolution. First, you need to buy one item, then sell it later. Find the best profit you can do.

Input:
A list of prices (integers), of length 2 or more.

Output:
The result of the best buy/sell operation, as an integer.

Example:
Given an array of prices [3, 10, 8, 4], the best profit you could make would be 7 because you buy at 3 first, then sell at 10.

Tests:
max_profit([10, 7, 5, 8, 11, 9])
max_profit([3, 4])
max_profit([9, 9])
max_profit([10, 7, 5, 4, 1])

Good luck!

This challenge comes from wontonst on CodeWars. Thank you to CodeWars, who has licensed redistribution of this challenge under the 2-Clause BSD License!

Want to propose a challenge idea for a future post? Email yo+challenge@dev.to with your suggestions!