You are given an integer array prices where prices[i] is the price of a given stock on the ith day.
On each day, you may decide to buy and/or sell the stock. You can only hold at most one share of the stock at any time. However, you can buy it then immediately sell it on the same day.
+ +Find and return the maximum profit you can achieve.
+ ++
Example 1:
+ ++Input: prices = [7,1,5,3,6,4] +Output: 7 +Explanation: Buy on day 2 (price = 1) and sell on day 3 (price = 5), profit = 5-1 = 4. +Then buy on day 4 (price = 3) and sell on day 5 (price = 6), profit = 6-3 = 3. +Total profit is 4 + 3 = 7. ++ +
Example 2:
+ ++Input: prices = [1,2,3,4,5] +Output: 4 +Explanation: Buy on day 1 (price = 1) and sell on day 5 (price = 5), profit = 5-1 = 4. +Total profit is 4. ++ +
Example 3:
+ ++Input: prices = [7,6,4,3,1] +Output: 0 +Explanation: There is no way to make a positive profit, so we never buy the stock to achieve the maximum profit of 0. ++ +
+
Constraints:
+ +1 <= prices.length <= 3 * 1040 <= prices[i] <= 104