# 714. Best Time to Buy and Sell Stock with Transaction Fee ⭐

Medium
You are given an array `prices` where `prices[i]` is the price of a given stock on the `ith` day, and an integer `fee` representing a transaction fee.
Find the maximum profit you can achieve. You may complete as many transactions as you like, but you need to pay the transaction fee for each transaction.
Note: You may not engage in multiple transactions simultaneously (i.e., you must sell the stock before you buy again).
Example 1:
Input: prices = [1,3,2,8,4,9], fee = 2
Output:
8
Explanation:
The maximum profit can be achieved by:
- Buying at prices = 1
- Selling at prices = 8
- Buying at prices = 4
- Selling at prices = 9
The total profit is ((8 - 1) - 2) + ((9 - 4) - 2) = 8.
Example 2:
Input: prices = [1,3,7,5,10,3], fee = 3
Output:
6
Constraints:
• `1 <= prices.length <= 5 * 10^4`
• `1 <= prices[i] < 5 * 10^4`
• `0 <= fee < 5 * 10^4`

### 解題

Runtime: 80 ms, faster than 100%
Memory Usage: 7.1 MdB, less than 96.92%
func maxProfit(prices []int, fee int) int {
if len(prices) <= 1 { return 0 }