Package g3501_3600.s3567_minimum_absolute_difference_in_sliding_submatrix

Class Solution

java.lang.Object

g3501_3600.s3567_minimum_absolute_difference_in_sliding_submatrix.Solution

public class Solution
extends Object

3567 - Minimum Absolute Difference in Sliding Submatrix.

Medium

You are given an m x n integer matrix grid and an integer k.

For every contiguous k x k submatrix of grid, compute the minimum absolute difference between any two distinct values within that submatrix.

Return a 2D array ans of size (m - k + 1) x (n - k + 1), where ans[i][j] is the minimum absolute difference in the submatrix whose top-left corner is (i, j) in grid.

Note: If all elements in the submatrix have the same value, the answer will be 0.

A submatrix (x1, y1, x2, y2) is a matrix that is formed by choosing all cells matrix[x][y] where x1 <= x <= x2 and y1 <= y <= y2.

Example 1:

Input: grid = [[1,8],[3,-2]], k = 2

Output: [[2]]

Explanation:

• There is only one possible k x k submatrix: \[\[1, 8], [3, -2]].
• Distinct values in the submatrix are [1, 8, 3, -2].
• The minimum absolute difference in the submatrix is |1 - 3| = 2. Thus, the answer is \[\[2]].

Example 2:

Input: grid = [[3,-1]], k = 1

Output: [[0,0]]

Explanation:

• Both k x k submatrix has only one distinct element.
• Thus, the answer is \[\[0, 0]].

Example 3:

Input: grid = [[1,-2,3],[2,3,5]], k = 2

Output: [[1,2]]

Explanation:

• There are two possible k × k submatrix:
  • Starting at (0, 0): \[\[1, -2], [2, 3]].
    • Distinct values in the submatrix are [1, -2, 2, 3].
    • The minimum absolute difference in the submatrix is |1 - 2| = 1.
  • Starting at (0, 1): \[\[-2, 3], [3, 5]].
    • Distinct values in the submatrix are [-2, 3, 5].
    • The minimum absolute difference in the submatrix is |3 - 5| = 2.
• Thus, the answer is \[\[1, 2]].

Constraints:

• 1 <= m == grid.length <= 30
• 1 <= n == grid[i].length <= 30
• -105 <= grid[i][j] <= 105
• 1 <= k <= min(m, n)

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int[][]	minAbsDiff(int[][] grid, int k)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Solution

public Solution()

Method Details

minAbsDiff

public int[][] minAbsDiff(int[][] grid,
 int k)