feat: add best time to buy and sell stock in python

Author: bujosa

alternative/easy/best_time_to_buy_and_sell_stock.py

@@ -0,0 +1,21 @@
+from typing import List
+
+# Best Time to Buy and Sell Stock
+def maxProfit(prices: List[int]) -> int:
+    maxProfit = 0
+    l, r = 0, 1
+
+    while r < len(prices):
+        if prices[l] < prices[r]:
+            profit = prices[r] - prices[l]
+            maxProfit = max(profit, maxProfit)
+        else:
+            l +=1
+        
+        r +=1
+        
+    return maxProfit
+
+
+assert maxProfit([7,1,5,3,6,4]) == 5
+assert maxProfit([7,6,4,3,1]) == 0