060. Best Time to Buy and Sell Stock.py

# Best Time to Buy and Sell Stock
"""

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.
"""


def maxProfit(self, prices):
    """
    :type prices: List[int]
    :rtype: int
    """
    # if 0 in prices:
    #     prices.remove(0)
    buy = prices[0]
    mx_profit = 0

    for i in range(1, len(prices)):
        profit = prices[i]-buy

        if profit > mx_profit:
            mx_profit = profit

        if buy > prices[i]:
            buy = prices[i]

    return (mx_profit)