Package g1001_1100.s1001_grid_illumination

Class Solution

java.lang.Object
g1001_1100.s1001_grid_illumination.Solution
public class Solution extends java.lang.Object
1001 - Grid Illumination.

Hard

There is a 2D grid of size n x n where each cell of this grid has a lamp that is initially turned off.

You are given a 2D array of lamp positions lamps, where lamps[i] = [rowi, coli] indicates that the lamp at grid[rowi][col<sub>i</sub>] is turned on. Even if the same lamp is listed more than once, it is turned on.

When a lamp is turned on, it illuminates its cell and all other cells in the same row, column, or diagonal.

You are also given another 2D array queries, where queries[j] = [rowj, colj]. For the jth query, determine whether grid[rowj][col<sub>j</sub>] is illuminated or not. After answering the jth query, turn off the lamp at grid[rowj][col<sub>j</sub>] and its 8 adjacent lamps if they exist. A lamp is adjacent if its cell shares either a side or corner with grid[rowj][col<sub>j</sub>].

Return an array of integers ans, where ans[j] should be 1 if the cell in the jth query was illuminated, or 0 if the lamp was not.

Example 1:

Input: n = 5, lamps = [[0,0],[4,4]], queries = [[1,1],[1,0]]

Output: [1,0]

Explanation: We have the initial grid with all lamps turned off. In the above picture we see the grid after turning on the lamp at grid[0][0] then turning on the lamp at grid[4][4]. The 0th query asks if the lamp at grid[1][1] is illuminated or not (the blue square). It is illuminated, so set ans[0] = 1. Then, we turn off all lamps in the red square. The 1st query asks if the lamp at grid[1][0] is illuminated or not (the blue square). It is not illuminated, so set ans[1] = 0. Then, we turn off all lamps in the red rectangle.

Example 2:

Input: n = 5, lamps = [[0,0],[4,4]], queries = [[1,1],[1,1]]

Output: [1,1]

Example 3:

Input: n = 5, lamps = [[0,0],[0,4]], queries = [[0,4],[0,1],[1,4]]

Output: [1,1,0]

Constraints:

  • 1 <= n <= 109
  • 0 <= lamps.length <= 20000
  • 0 <= queries.length <= 20000
  • lamps[i].length == 2
  • 0 <= rowi, coli < n
  • queries[j].length == 2
  • 0 <= rowj, colj < n

  • Constructor Summary

    Constructors
    Constructor
    Description
    Solution()
     

  • Method Summary

    Modifier and Type
    Method
    Description
    int[]
    gridIllumination(int n, int[][] lamps, int[][] queries)
     

    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

    • gridIllumination

      public int[] gridIllumination(int n, int[][] lamps, int[][] queries)