<span>leetcode-1072 Flip Columns For Maximum Number of Equal Rows</span>
Given a matrix consisting of 0s and 1s, we may choose any number of columns in the matrix and flip every cell in that column. Flipping a cell changes the value of that cell from 0 to 1 or from 1 to 0. Return the maximum number of rows that have all values equal after some number of flips.
输入输出实例：
Input: [[0,1],[1,1]] Output: 1 Explanation: After flipping no values, 1 row has all values equal.
本题可以使用dict，统计最多的相同的行出现的次数（row 和 reverse(row)视为同一行）
class Solution: def maxEqualRowsAfterFlips(self, matrix: List[List[int]]) -> int: def reverse_row(arr): res = [0] * len(arr) for item, values in enumerate(row): res[item] = 1 - values return res dic = {} for row in matrix: if tuple(row) in dic: dic[tuple(row)] += 1 elif tuple(reverse_row(row)) in dic: dic[tuple(reverse_row(row))] += 1 else: dic[tuple(row)] = 1 dic = sorted(dic.items(), key = lambda x:x[1], reverse=True) return dic[0][1]
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