{ "data": { "question": { "questionId": "1242", "questionFrontendId": "1314", "boundTopicId": null, "title": "Matrix Block Sum", "titleSlug": "matrix-block-sum", "content": "

Given a m x n matrix mat and an integer k, return a matrix answer where each answer[i][j] is the sum of all elements mat[r][c] for:

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Example 1:

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\nInput: mat = [[1,2,3],[4,5,6],[7,8,9]], k = 1\nOutput: [[12,21,16],[27,45,33],[24,39,28]]\n
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Example 2:

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\nInput: mat = [[1,2,3],[4,5,6],[7,8,9]], k = 2\nOutput: [[45,45,45],[45,45,45],[45,45,45]]\n
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Constraints:

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