Maximum Building Height LeetCode solution in Python

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# Readability version
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class Solution:
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    def maxBuilding(self, n: int, restrictions: List[List[int]]) -> int:
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        # Set the initial height for the 1st building
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        restrictions.append([1, 0])
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        restrictions.sort()
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        # Process restrictions to find the valid ones for reaching previous restrictions
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        valid_restrictions_forward = []
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        temp_diff = 0
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        for id, ht in restrictions:
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            current_diff = id - ht
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            if current_diff >= temp_diff:
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                temp_diff = current_diff
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                valid_restrictions_forward.append([id, ht])
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        # Process valid restrictions backward to find the ones for reaching next restrictions
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        valid_restrictions_backward = []
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        temp_sum = n + n - 1
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        for id, ht in valid_restrictions_forward[::-1]:
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            current_sum = id + ht
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            if current_sum <= temp_sum:
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                temp_sum = current_sum
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                valid_restrictions_backward.append([id, ht])
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        # Reverse the backward valid restrictions to get the correct order
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        valid_restrictions_backward.reverse()
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        # Add maximum height for the last building due to the last restriction
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        if valid_restrictions_backward[-1][0] != n:
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            valid_restrictions_backward.append(
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                [
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                    n,
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                    valid_restrictions_backward[-1][1]
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                    + n
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                    - valid_restrictions_backward[-1][0],
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                ]
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            )
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        # Calculate the maximum height
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        max_height = 0
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        for i in range(len(valid_restrictions_backward) - 1):
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            x1, y1 = valid_restrictions_backward[i]
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            x2, y2 = valid_restrictions_backward[i + 1]
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            available_height = (-x1 + y1 + x2 + y2) // 2
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            if available_height > max_height:
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                max_height = available_height
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        return max_height