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* commit on 'shortest_path_sum' * minimum_path_sum updated * commit to 'minimum_path_sum' * added description to minimum_path_sum * bot requirements fixed for * Update minimum_path_sum.py * Update minimum_path_sum.py Co-authored-by: John Law <johnlaw.po@gmail.com>
64 lines
1.5 KiB
Python
64 lines
1.5 KiB
Python
def min_path_sum(grid: list) -> int:
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"""
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Find the path from top left to bottom right of array of numbers
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with the lowest possible sum and return the sum along this path.
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>>> min_path_sum([
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... [1, 3, 1],
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... [1, 5, 1],
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... [4, 2, 1],
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... ])
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7
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>>> min_path_sum([
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... [1, 0, 5, 6, 7],
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... [8, 9, 0, 4, 2],
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... [4, 4, 4, 5, 1],
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... [9, 6, 3, 1, 0],
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... [8, 4, 3, 2, 7],
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... ])
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20
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>>> min_path_sum(None)
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Traceback (most recent call last):
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...
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TypeError: The grid does not contain the appropriate information
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>>> min_path_sum([[]])
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Traceback (most recent call last):
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...
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TypeError: The grid does not contain the appropriate information
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"""
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if not grid or not grid[0]:
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raise TypeError("The grid does not contain the appropriate information")
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for cell_n in range(1, len(grid[0])):
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grid[0][cell_n] += grid[0][cell_n - 1]
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row_above = grid[0]
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for row_n in range(1, len(grid)):
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current_row = grid[row_n]
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grid[row_n] = fill_row(current_row, row_above)
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row_above = grid[row_n]
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return grid[-1][-1]
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def fill_row(current_row: list, row_above: list) -> list:
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"""
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>>> fill_row([2, 2, 2], [1, 2, 3])
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[3, 4, 5]
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"""
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current_row[0] += row_above[0]
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for cell_n in range(1, len(current_row)):
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current_row[cell_n] += min(current_row[cell_n - 1], row_above[cell_n])
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return current_row
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if __name__ == "__main__":
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import doctest
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doctest.testmod()
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