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How to Solve Find a Good Subset of the Matrix Problem
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Hard#2732
LeetCode ProblemFind a Good Subset of the Matrix
You are given a 0-indexed m x n binary matrix grid. Let us call a non-empty subset of rows good if the sum of each column of the subset is at most half of the length of the subset. More formally, if the length of the chosen subset of rows is k, then the sum of each column should be at most floor(k / 2). Return an integer array that contains row indices of a good subset sorted in ascending order. If there are multiple good subsets, you can return any of them. If there are no good subsets, return an empty array. A subset of rows of the matrix grid is any matrix that can be obtained by deleting some (possibly none or all) rows from grid.
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Problem Breakdown
Understanding the Find a Good Subset of the Matrix Problem
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Problem Statement
You are given a 0-indexed m x n binary matrix grid. Let us call a non-empty subset of rows good if the sum of each column of the subset is at most half of the length of the subset. More formally, if the length of the chosen subset of rows is k, then the sum of each column should be at most floor(k / 2). Return an integer array that contains row indices of a good subset sorted in ascending order. If there are multiple good subsets, you can return any of them. If there are no good subsets, return an empty array. A subset of rows of the matrix grid is any matrix that can be obtained by deleting some (possibly none or all) rows from grid.
HardProblem #2732
LeetCodeFind a Good Subset of the Matrix
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Examples
# Example 1
Input
grid = [[0,1,1,0],[0,0,0,1],[1,1,1,1]]
Output
[0,1]
# Example 2
Input
grid = [[0]]
Output
[0]
# Example 3
Input
grid = [[1,1,1],[1,1,1]]
Output
[]
Constraints
m == grid.length
n == grid[i].length
1 <= m <= 104
1 <= n <= 5
grid[i][j] is either 0 or 1.
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Solve Find a Good Subset of the Matrix — You are given a 0-indexed m x n binary matrix grid. Let us call a non-empty subs...
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def solve(input):
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Time: O(n) | Space: O(n)
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Frequently Asked Questions
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