Completed Competitive-Coding-10 : Please review.

BuyAndSell2.py

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+# Time Complexity : O(n) 
+# Space Complexity :O(1)
+# Did this code successfully run on Leetcode : Yes
+# Any problem you faced while coding this : No
+# Your code here along with comments explaining your approach
+class Solution:
+    def maxProfit(self, prices: List[int]) -> int:
+        if len(prices) <= 1:
+            return 0 
+        profit = 0 
+        i = 0 
+        while i < len(prices):
+
+            while i < len(prices)-1 and prices[i+1] <= prices[i]:
+                i += 1 
+            min_ = prices[i]
+            i += 1 
+
+            while i < len(prices)-1 and prices[i+1] >= prices[i]:
+                i+= 1 
+
+            if i < len(prices):
+                profit += prices[i] - min_
+                i += 1 
+
+        return profit

PeekingIterator.py

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+# Did this code successfully run on Leetcode : Yes
+# Any problem you faced while coding this : No
+# Your code here along with comments explaining your approach
+class PeekingIterator:
+    temp = None 
+    def __init__(self, iterator):
+        """
+        Initialize your data structure here.
+        :type iterator: Iterator
+        """
+        self.itr = iterator
+        if self.itr.hasNext():
+            self.temp = self.itr.next()
+
+    # Time = O(1) | Space = O(1)
+    def peek(self):
+        """
+        Returns the next element in the iteration without advancing the iterator.
+        :rtype: int
+        """
+        return self.temp
+
+    # Time = O(1) | Space = O(1)
+    def next(self):
+        """
+        :rtype: int
+        """
+        prev = self.temp 
+        if self.itr.hasNext():
+            self.temp = self.itr.next()
+        else:
+            self.temp = None 
+        return prev 
+
+    # Time = O(1) | Space = O(1)
+    def hasNext(self):
+        """
+        :rtype: bool
+        """
+        if self.temp is not None :
+            return True 
+        else:
+            return False