Practice Number of Black Blocks

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Medium#2768

LeetCode Problem

Number of Black Blocks

Array Hash Table Enumeration

Problem Statement

You are given two integers m and n representing the dimensions of a 0-indexed m x n grid. You are also given a 0-indexed 2D integer matrix coordinates, where coordinates[i] = [x, y] indicates that the cell with coordinates [x, y] is colored black. All cells in the grid that do not appear in coordinates are white. A block is defined as a 2 x 2 submatrix of the grid. More formally, a block with cell [x, y] as its top-left corner where 0 <= x < m - 1 and 0 <= y < n - 1 contains the coordinates [x, y], [x + 1, y], [x, y + 1], and [x + 1, y + 1]. Return a 0-indexed integer array arr of size 5 such that arr[i] is the number of blocks that contains exactly i black cells.

Source: Number of Black Blocks on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input

m = 3, n = 3, coordinates = [[0,0]]

Output

[3,1,0,0,0]

# Example 2

Input

m = 3, n = 3, coordinates = [[0,0],[1,1],[0,2]]

Output

[0,2,2,0,0]

Constraints

2 <= m <= 10^5

2 <= n <= 10^5

0 <= coordinates.length <= 10^4

coordinates[i].length == 2

0 <= coordinates[i][0] < m

0 <= coordinates[i][1] < n

It is guaranteed that coordinates contains pairwise distinct coordinates.

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