1314. Matrix Block Sum

LeetCodeArrayMatrixPrefix SumOpen on judge ↗

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: - i - k <= r <= i + k, - j - k <= c <= j + k, and - (r, c) is a valid position in the matrix. Example 1: Input: mat = [[1,2,3],[4,5,6],[7,8,9]], k = 1 Output: [[12,21,16],[27,45,33],[24,39,28]] Example 2: Input: mat = [[1,2,3],[4,5,6],[7,8,9]], k = 2 Output:

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solution.cppC++17

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