solution of two sum problem

buy_and_sell_stocks/buy-sell-stocks.py

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+from typing import List
+
+
+class Solution:
+    def maxProfit(self, prices: List[int]) -> int:
+        lowest_price = prices[0]
+        max_profit = 0
+        for price in prices:
+            if price < lowest_price:
+                lowest_price = price
+            elif price - lowest_price > max_profit:
+                max_profit = price - lowest_price
+        return max_profit

two-sum/two-sum.py

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+from typing import List
+
+
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        answer: List[int] = []
+        for i in range(len(nums)):
+            for j in range(len(nums)):
+                if nums[i] + nums[j] == target and i != j:
+                    answer.append(i)
+                    answer.append(j)
+                    return answer