longest_abs_path.py

# def lengthLongestPath(input):
# maxlen = 0
# pathlen = {0: 0}
# for line in input.splitlines():
# print("---------------")
# print("line:", line)
# name = line.strip('\t')
# print("name:", name)
# depth = len(line) - len(name)
# print("depth:", depth)
# if '.' in name:
# maxlen = max(maxlen, pathlen[depth] + len(name))
# else:
# pathlen[depth + 1] = pathlen[depth] + len(name) + 1
# print("maxlen:", maxlen)
# return maxlen

# def lengthLongestPath(input):
# paths = input.split("\n")
# level = [0] * 10
# maxLength = 0
# for path in paths:
# print("-------------")
# levelIdx = path.rfind("\t")
# print("Path: ", path)
# print("path.rfind(\\t)", path.rfind("\t"))
# print("levelIdx: ", levelIdx)
# print("level: ", level)
# level[levelIdx + 1] = level[levelIdx] + len(path) - levelIdx + 1
# print("level: ", level)
# if "." in path:
# maxLength = max(maxLength, level[levelIdx+1] - 1)
# print("maxlen: ", maxLength)
# return maxLength


def length_longest_path(input):
    """
    :type input: str
    :rtype: int
    """
    currlen, maxlen = 0, 0  # running length and max length
    stack = []  # keep track of the name length
    for s in input.split('\n'):
        print("---------")
        print("<path>:", s)
        depth = s.count('\t')  # the depth of current dir or file
        print("depth: ", depth)
        print("stack: ", stack)
        print("curlen: ", currlen)
        while len(stack) > depth:  # go back to the correct depth
            currlen -= stack.pop()
        stack.append(len(s.strip('\t')) + 1)  # 1 is the length of '/'
        currlen += stack[-1]  # increase current length
        print("stack: ", stack)
        print("curlen: ", currlen)
        if '.' in s:  # update maxlen only when it is a file
            maxlen = max(maxlen, currlen - 1)  # -1 is to minus one '/'
    return maxlen


st = ("dir\n\tsubdir1\n\t\tfile1.ext\n\t\tsubsubdirectory1\n\t"
      "subdir2\n\t\tsubsubdir2\n\t\t\tfile2.ext")
st2 = "a\n\tb1\n\t\tf1.txt\n\taaaaa\n\t\tf2.txt"
print("path:", st2)

print("answer:", length_longest_path(st2))