Build the file system like a multi-branched tree, each tree node is either a directory or a file.
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(False, "", {a, a2}) # home dir
/ \
/ \
{ (False, "", {}), (False, "", {b}) } #a, a2 dir
|
{ (False, "", {c, file_in_b}) } #b dir
/\
/ \
{ (False, "", {}), (True, "content", {}) } # c dir, file_in_b
class Node:
def __init__(self):
self.is_file = False
self.file_content = ""
self.children = {} # key is dir or file name
class FileSystem:
def __init__(self):
self.fs = Node()
def ls(self, path):
"""
:type path: str
:rtype: List[str]
"""
node = self.fs
# omit empty string
dirs = [dir for dir in path.split('/') if dir.strip() != '']
ans = []
# if path = '/', this for loop will be skipped
for dir in dirs:
if dir not in node.children:
return ans
node = node.children[dir]
if node.is_file:
ans.append(dirs[-1])
else:
for k, _ in node.children.items():
ans.append(k)
return sorted(ans)
def mkdir(self, path):
"""
:type path: str
:rtype: void
"""
node = self.fs
dirs = [dir for dir in path.split('/') if dir.strip() != '']
for dir in dirs:
if dir not in node.children:
node.children[dir] = Node()
node = node.children[dir]
def addContentToFile(self, filePath, content):
"""
:type filePath: str
:type content: str
:rtype: void
"""
node = self.fs
dirs = [dir for dir in filePath.split('/') if dir.strip() != '']
for dir in dirs:
if dir not in node.children:
node.children[dir] = Node()
node = node.children[dir]
# mark it as a file
node.is_file = True
# append content to it, default content is empty string
node.file_content += content
def readContentFromFile(self, filePath):
"""
:type filePath: str
:rtype: str
"""
node = self.fs
dirs = [dir for dir in filePath.split('/') if dir.strip() != '']
for dir in dirs:
if dir not in node.children:
node.children[dir] = Node()
node = node.children[dir]
return node.file_content
# Your FileSystem object will be instantiated and called as such:
# obj = FileSystem()
# param_1 = obj.ls(path)
# obj.mkdir(path)
# obj.addContentToFile(filePath,content)
# param_4 = obj.readContentFromFile(filePath)
