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How to Solve Image Smoother Problem
Master the Image Smoother 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.
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Start Free for WindowsEasy#661
LeetCode ProblemImage Smoother
An image smoother is a filter of the size 3 x 3 that can be applied to each cell of an image by rounding down the average of the cell and the eight surrounding cells (i.e., the average of the nine cells in the blue smoother). If one or more of the surrounding cells of a cell is not present, we do not consider it in the average (i.e., the average of the four cells in the red smoother). Given an m x n integer matrix img representing the grayscale of an image, return the image after applying the smoother on each cell of it.
ArrayMatrix
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Problem Breakdown
Understanding the Image Smoother Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
An image smoother is a filter of the size 3 x 3 that can be applied to each cell of an image by rounding down the average of the cell and the eight surrounding cells (i.e., the average of the nine cells in the blue smoother). If one or more of the surrounding cells of a cell is not present, we do not consider it in the average (i.e., the average of the four cells in the red smoother). Given an m x n integer matrix img representing the grayscale of an image, return the image after applying the smoother on each cell of it.
EasyProblem #661
LeetCodeImage Smoother
Related Topics
ArrayMatrix
How Phantom Code Helps
Get real-time assistance for Image Smoother problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
img = [[1,1,1],[1,0,1],[1,1,1]]
Output
[[0,0,0],[0,0,0],[0,0,0]]
# Example 2
Input
img = [[100,200,100],[200,50,200],[100,200,100]]
Output
[[137,141,137],[141,138,141],[137,141,137]]
Constraints
m == img.length
n == img[i].length
1 <= m, n <= 200
0 <= img[i][j] <= 255
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Solve Image Smoother — An image smoother is a filter of the size 3 x 3 that can be applied to each cell...
Here's the optimal approach using Array:
def solve(input):
# Optimal O(n) solution
return result
Time: O(n) | Space: O(n)
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Undetectability Checklist
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Platform Compatibility
Zoom
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Google Meet
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HackerRank
Supported
CodeSignal
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CoderPad
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Teams
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Frequently Asked Questions
Common questions about solving Image Smoother and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Image Smoother during interviews?
Phantom Code generates complete solutions instantly with proper complexity analysis, letting you focus on explaining your approach and demonstrating problem-solving skills rather than getting stuck on implementation details during high-pressure situations.
What if the interviewer asks follow-up questions or modifications to problems like Image Smoother?
Phantom Code adapts in real-time. Screenshot the modified problem or use audio mode to capture the interviewer's follow-up, and get an updated solution within seconds — including edge cases and optimizations.
Can Phantom Code help me communicate my solution for problems like Image Smoother?
Yes. Phantom Code provides step-by-step approach explanations with 3 progressive thoughts, so you can walk through your solution naturally. It also provides time and space complexity analysis to discuss trade-offs.
How does Phantom Code assist with different programming languages for Image Smoother type problems?
Phantom Code supports 11 programming languages including Python, Java, C++, JavaScript, TypeScript, Go, Rust, Ruby, Swift, Kotlin, and C#. Set your preferred language and get idiomatic solutions.
What coding mistakes does Phantom Code help me avoid during Image Smoother interviews?
Phantom Code catches common mistakes like off-by-one errors, missing edge cases, incorrect base conditions, and suboptimal approaches. It provides clean, well-structured code that handles all edge cases.
Is Phantom Code detectable when solving problems like Image Smoother during live interviews?
No. Phantom Code runs as an invisible desktop overlay that doesn't appear in screen shares, recordings, or proctoring software. It works with Zoom, HackerRank, CodeSignal, CoderPad, and all major platforms.
How does Phantom Code help when I'm struggling with Image Smoother style questions under pressure?
The AI provides structured guidance: first the approach (what algorithm/data structure to use and why), then the implementation with clean code, and finally complexity analysis. This helps you think clearly even under pressure.
Does Phantom Code work for the coding platforms used in Image Smoother interviews?
Yes. Phantom Code works with all major coding platforms including LeetCode, HackerRank, CodeSignal, CoderPad, HackerEarth, and any browser-based coding environment.
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