Master the Grid Illumination LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
Phantom Code generates complete solutions and debugging hints that you can use while explaining your approach, so you stay calm and in control.
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][coli] 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][colj] is illuminated or not. After answering the jth query, turn off the lamp at grid[rowj][colj] and its 8 adjacent lamps if they exist. A lamp is adjacent if its cell shares either a side or corner with grid[rowj][colj]. 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.
Phantom Code will help you solve this problem in real-time during your interview
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
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][coli] 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][colj] is illuminated or not. After answering the jth query, turn off the lamp at grid[rowj][colj] and its 8 adjacent lamps if they exist. A lamp is adjacent if its cell shares either a side or corner with grid[rowj][colj]. 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.
Get real-time assistance for Grid Illumination problems during coding interviews. Phantom Code provides instant solutions and explanations.
n = 5, lamps = [[0,0],[4,4]], queries = [[1,1],[1,0]]
[1,0]
n = 5, lamps = [[0,0],[4,4]], queries = [[1,1],[1,1]]
[1,1]
n = 5, lamps = [[0,0],[0,4]], queries = [[0,4],[0,1],[1,4]]
[1,1,0]
Reinforce undetectability, platform compatibility, and real-time assistance to remove any doubt.
Watch how Phantom Code helps solve LeetCode problems during live interviews
Solve Grid Illumination — There is a 2D grid of size n x n where each cell of this grid has a lamp that is...
Here's the optimal approach using Array:
Time: O(n) | Space: O(n)
Thousands of developers use Phantom Code. Social proof signals that this approach helps real candidates land offers across a range of companies.
Our native desktop architecture avoids common detection vectors used by browser extensions. We provide a clear checklist so you can run basic checks and confirm the app will be invisible.
We work with Zoom, HackerRank, CodeSignal, CoderPad and other web-based platforms. Check the compatibility note and request a browser link if a specific desktop app is unsupported.
Common questions about solving Grid Illumination and using Phantom Code during coding interviews.
The only AI interview tool with an undetectable desktop overlay, real-time audio listening, and personalized AI responses.