{ "data": { "question": { "questionId": "1147", "questionFrontendId": "1072", "boundTopicId": null, "title": "Flip Columns For Maximum Number of Equal Rows", "titleSlug": "flip-columns-for-maximum-number-of-equal-rows", "content": "

You are given an m x n binary matrix matrix.

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You can choose any number of columns in the matrix and flip every cell in that column (i.e., Change the value of the cell from 0 to 1 or vice versa).

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Return the maximum number of rows that have all values equal after some number of flips.

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Example 1:

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\nInput: matrix = [[0,1],[1,1]]\nOutput: 1\nExplanation: After flipping no values, 1 row has all values equal.\n
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Example 2:

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\nInput: matrix = [[0,1],[1,0]]\nOutput: 2\nExplanation: After flipping values in the first column, both rows have equal values.\n
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Example 3:

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\nInput: matrix = [[0,0,0],[0,0,1],[1,1,0]]\nOutput: 2\nExplanation: After flipping values in the first two columns, the last two rows have equal values.\n
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Constraints:

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