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How to Solve Delete Duplicate Folders in System Problem
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LeetCode ProblemDelete Duplicate Folders in System
Due to a bug, there are many duplicate folders in a file system. You are given a 2D array paths, where paths[i] is an array representing an absolute path to the ith folder in the file system. Two folders (not necessarily on the same level) are identical if they contain the same non-empty set of identical subfolders and underlying subfolder structure. The folders do not need to be at the root level to be identical. If two or more folders are identical, then mark the folders as well as all their subfolders. Once all the identical folders and their subfolders have been marked, the file system will delete all of them. The file system only runs the deletion once, so any folders that become identical after the initial deletion are not deleted. Return the 2D array ans containing the paths of the remaining folders after deleting all the marked folders. The paths may be returned in any order.
ArrayHash TableStringTrieHash Function
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Problem Breakdown
Understanding the Delete Duplicate Folders in System Problem
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Problem Statement
Due to a bug, there are many duplicate folders in a file system. You are given a 2D array paths, where paths[i] is an array representing an absolute path to the ith folder in the file system. Two folders (not necessarily on the same level) are identical if they contain the same non-empty set of identical subfolders and underlying subfolder structure. The folders do not need to be at the root level to be identical. If two or more folders are identical, then mark the folders as well as all their subfolders. Once all the identical folders and their subfolders have been marked, the file system will delete all of them. The file system only runs the deletion once, so any folders that become identical after the initial deletion are not deleted. Return the 2D array ans containing the paths of the remaining folders after deleting all the marked folders. The paths may be returned in any order.
HardProblem #1948
LeetCodeDelete Duplicate Folders in System
Related Topics
ArrayHash TableStringTrieHash Function
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Examples
# Example 1
Input
paths = [["a"],["c"],["d"],["a","b"],["c","b"],["d","a"]]
Output
[["d"],["d","a"]]
# Example 2
Input
paths = [["a"],["c"],["a","b"],["c","b"],["a","b","x"],["a","b","x","y"],["w"],["w","y"]]
Output
[["c"],["c","b"],["a"],["a","b"]]
# Example 3
Input
paths = [["a","b"],["c","d"],["c"],["a"]]
Output
[["c"],["c","d"],["a"],["a","b"]]
Constraints
1 <= paths.length <= 2 * 104
1 <= paths[i].length <= 500
1 <= paths[i][j].length <= 10
1 <= sum(paths[i][j].length) <= 2 * 105
path[i][j] consists of lowercase English letters.
No two paths lead to the same folder.
For any folder not at the root level, its parent folder will also be in the input.
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Solve Delete Duplicate Folders in System — Due to a bug, there are many duplicate folders in a file system. You are given a...
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Frequently Asked Questions
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What coding mistakes does Phantom Code help me avoid during Delete Duplicate Folders in System 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.
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How does Phantom Code help when I'm struggling with Delete Duplicate Folders in System 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 Delete Duplicate Folders in System 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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