609.FindDuplicateFileinSystem.py

"""
    Given a list of directory info including directory path, and all the files 
    with contents in this directory, you need to find out all the groups of 
    duplicate files in the file system in terms of their paths.
    A group of duplicate files consists of at least two files that have exactly 
    the same content.
    
    A single directory info string in the input list has the following format:
        "root/d1/d2/.../dm f1.txt(f1_content) f2.txt(f2_content) ... fn.txt(fn_content)"

    It means there are n files 
    (f1.txt, f2.txt ... fn.txt with content f1_content, f2_content ... 
                     fn_content, respectively) in directory root/d1/d2/.../dm. 
    Note that n >= 1 and m >= 0. If m = 0, it means the directory is just the 
    root directory.
    
    The output is a list of group of duplicate file paths. For each group, it 
    contains all the file paths of the files that have the same content. 
    A file path is a string that has the following format:
        "directory_path/file_name.txt"
    
    Example:
    Input:
    ["root/a 1.txt(abcd) 2.txt(efgh)", "root/c 3.txt(abcd)", "root/c/d 4.txt(efgh)", "root 4.txt(efgh)"]
    Output:  
    [["root/a/2.txt","root/c/d/4.txt","root/4.txt"],["root/a/1.txt","root/c/3.txt"]]
      
    Note:
    1. No order is required for the final output.
    2. You may assume the directory name, file name and file content only has 
       letters and digits, and the length of file content is in the range of [1,50].
    3. The number of files given is in the range of [1,20000].
    4. You may assume no files or directories share the same name in the same 
       directory.
    5. You may assume each given directory info represents a unique directory. 
       Directory path and file info are separated by a single blank space.
     
    Follow-up beyond contest:
    1. Imagine you are given a real file system, how will you search files? 
       DFS or BFS?
    2. If the file content is very large (GB level), how will you modify your 
       solution?
    3. If you can only read the file by 1kb each time, how will you modify your 
       solution?
    4. What is the time complexity of your modified solution? What is the most 
       time-consuming part and memory consuming part of it? How to optimize?
    5. How to make sure the duplicated files you find are not false positive?
"""
#Difficulty: Medium
#161 / 161 test cases passed.
#Runtime: 80 ms
#Memory Usage: 23.3 MB

#Runtime: 80 ms, faster than 97.25% of Python3 online submissions for Find Duplicate File in System.
#Memory Usage: 23.3 MB, less than 36.36% of Python3 online submissions for Find Duplicate File in System.

class Solution:
    def findDuplicate(self, paths: List[str]) -> List[List[str]]:
        db = {}
        for path in paths:
            files = path.split(' ')
            root = files[0]
            for file in files[1:]:
                filename, content = file.replace(r')', '').split(r'(')
                if content not in db:
                    db[content] = [root+'/'+filename]
                else:
                    db[content].append(root+'/'+filename)
        return [value for value in db.values() if len(value) > 1]