1072. Flip Columns For Maximum Number of Equal Rows

# 1072. Flip Columns For Maximum Number of Equal Rows

## 刷题内容

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.

Example 1:

Input: [[0,1],[1,1]]
Output: 1
Explanation: After flipping no values, 1 row has all values equal.
Example 2:

Input: [[0,1],[1,0]]
Output: 2
Explanation: After flipping values in the first column, both rows have equal values.
Example 3:

Input: [[0,0,0],[0,0,1],[1,1,0]]
Output: 2
Explanation: After flipping values in the first two columns, the last two rows have equal values.

Note:

1 <= matrix.length <= 300
1 <= matrix[i].length <= 300
All matrix[i].length's are equal
matrix[i][j] is 0 or 1

*- 时间复杂度: O(m * n)- 空间复杂度: O(m)*

• 对于某一行，我们如果想让它那一行元素全部相等的话，我们要不全部变成1，要不全部变成0
• 对于任意两行，如果他们的某一列的cell相等，那么无论这列被翻转多少次，这两列都是一样的
• 对于任意两行，如果他们的某一列的cell不相等，那么无论这列被翻转多少次，这两列都不会一样

`python
class Solution: