#2373

Largest Local Values in a Matrix

newbie · 110 · lc easy +12 · verified · 87.7% accepted · 1,323 likes · top 98%

Description

Given an n x n integer matrix grid, produce a (n - 2) x (n - 2) output matrix maxLocal where each entry maxLocal[i][j] equals the maximum value found in the 3 x 3 subgrid of grid centered at row i + 1 and column j + 1.

Return the generated matrix.

Example 1:

Input: grid = [[9,9,8,1],[5,6,2,6],[8,2,6,4],[6,2,2,2]]

Output: [[9,9],[8,6]]

Explanation: The diagram above shows the original matrix and the generated matrix.

Notice that each value in the generated matrix corresponds to the largest value of a contiguous 3 x 3 matrix in grid.

Example 2:

Input: grid = [[1,1,1,1,1],[1,1,1,1,1],[1,1,2,1,1],[1,1,1,1,1],[1,1,1,1,1]]

Output: [[2,2,2],[2,2,2],[2,2,2]]

Explanation: Notice that the 2 is contained within every contiguous 3 x 3 matrix in grid.

Code

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class Solution:
    def largestLocal(self, grid: List[List[int]]) -> List[List[int]]:

class Solution:
    def largestLocal(self, grid: List[List[int]]) -> List[List[int]]: