from functools import reduce


def min_column_widths(rows):
    """Computes the minimum column width for the table of strings.

    >>> min_column_widths([["some", "fields"], ["other", "line"]])
    [5, 6]
    """
    def lengths(row): return map(len, row)
    def maximums(row1, row2) : return map(max, row1, row2)
    return reduce(maximums, map(lengths, rows))