# 71. Simplify Path

# Given a string path, which is an absolute path(starting with a slash '/') to a file or directory in a Unix-style file system, convert it to the simplified canonical path.
# In a Unix-style file system, a period '.' refers to the current directory, a double period '..' refers to the directory up a level, and any multiple consecutive slashes(i.e. '//') are treated as a single slash '/'. For this problem, any other format of periods such as '...' are treated as file/directory names.
# The canonical path should have the following format:
# The path starts with a single slash '/'.
# Any two directories are separated by a single slash '/'.
# The path does not end with a trailing '/'.
# The path only contains the directories on the path from the root directory to the target file or directory(i.e., no period '.' or double period '..')
# Return the simplified canonical path.

# Example 1:
# Input: path = "/home/"
# Output: "/home"
# Explanation: Note that there is no trailing slash after the last directory name.

# Example 2:
# Input: path = "/../"
# Output: "/"
# Explanation: Going one level up from the root directory is a no-op, as the root level is the highest level you can go.

# Example 3:
# Input: path = "/home//foo/"
# Output: "/home/foo"
# Explanation: In the canonical path, multiple consecutive slashes are replaced by a single one.

# Example 4:
# Input: path = "/a/./b/../../c/"
# Output: "/c"


class Solution(object):
    def simplifyPath(self, path):
        stack = []

        for p in path.split("/"):
            if p == "..":
                if stack:
                    stack.pop()
            elif p and p != '.':
                stack.append(p)

        return '/' + '/'.join(stack)
