Create 121.py

Author: Itskoushik

121 Leetcode/121.py

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+class Solution:
+    def maxProfit(self, prices: List[int]) -> int:
+        # Initialize two pointers: left (buy day) and right (sell day)
+        l, r = 0, 1  
+        
+        # Variable to store the maximum profit
+        maxp = 0  
+
+        # Iterate through the price list
+        while r < len(prices):
+            # If the current price is greater than the buying price, calculate profit
+            if prices[l] < prices[r]:
+                profit = prices[r] - prices[l]  # Profit if we buy at prices[l] and sell at prices[r]
+                maxp = max(maxp, profit)  # Update max profit if current profit is greater
+            else:
+                # If the price at r is lower than at l, move the buy pointer to r
+                l = r  
+            
+            # Move the sell pointer to the next day
+            r += 1  
+
+        # Return the maximum profit found
+        return maxp