Design an in-memory file system to simulate the following functions:
ls
: Given a path in string format. If it is a file path, return a list that only contains this file's name. If it is a directory path, return the list of file and directory names
in this directory
. Your output (file and directory names together) should in
lexicographic order
.
mkdir
: Given a
directory path
that does not exist, you should make a new directory according to the path. If the middle directories in the path don't exist either, you should create them as well. This function has void return type.
addContentToFile
: Given a
file path
and
file content
in string format. If the file doesn't exist, you need to create that file containing given content. If the file already exists, you need to
append
given content to original content. This function has void return type.
readContentFromFile
: Given a
file path
, return its
content
in string format.
Example:
Input: ["FileSystem","ls","mkdir","addContentToFile","ls","readContentFromFile"] [[],["/"],["/a/b/c"],["/a/b/c/d","hello"],["/"],["/a/b/c/d"]] Output: [null,[],null,null,["a"],"hello"] Explanation:
Note:
/
and do not end with
/
except that the path is just
"/"
.