Minimum Falling Path Sum II LeetCode solution in Python

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class Solution:
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    def minFallingPathSum(self, grid: List[List[int]]) -> int:
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        m, n = len(grid), len(grid[0])
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        if m == 1 and n == 1:
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            return grid[0][0]
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        min_arr = [0 for _ in range(n)]
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        for i in range(m):
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            prefix = [float("inf") for _ in range(n)]
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            suffix = [float("inf") for _ in range(n)]
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            current_row = [elem1 + elem2 for elem1, elem2 in zip(grid[i], min_arr)]
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            for i in range(1, n):
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                prefix[i] = min(prefix[i - 1], current_row[i - 1])
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            for i in range(n - 2, -1, -1):
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                suffix[i] = min(suffix[i + 1], current_row[i + 1])
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            min_arr = [min(pre, suff) for pre, suff in zip(prefix, suffix)]
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        return min(min_arr)