Remove Sub-Folders from the Filesystem
Given a list of folders folder, return the folders after removing all sub-folders in those folders. You may return the answer in any order.
If a folder[i] is located within another folder[j], it is called a sub-folder of it. A sub-folder of folder[j] must start with folder[j], followed by a "/". For example, "/a/b" is a sub-folder of "/a", but "/b" is not a sub-folder of "/a/b/c".
The format of a path is one or more concatenated strings of the form: '/' followed by one or more lowercase English letters.
- For example,
"/leetcode"and"/leetcode/problems"are valid paths while an empty string and"/"are not.
Example 1
Input
folder = ["/a","/a/b","/c/d","/c/d/e","/c/f"]Output
["/a","/c/d","/c/f"]Folders "/a/b" is a subfolder of "/a" and "/c/d/e" is inside of folder "/c/d" in our filesystem.
Example 2
Input
folder = ["/a","/a/b/c","/a/b/d"]Output
["/a"]Folders "/a/b/c" and "/a/b/d" will be removed because they are subfolders of "/a".
Constraints
- 1 <= folder.length <= 4 * 10^4
- 2 <= folder[i].length <= 100
- folder[i] contains only lowercase letters and '/'.
- folder[i] always starts with the character '/'.
- Each folder name is unique.
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