solution to longest absolute path

test_1 = "dir\n\tsubdir1\n\t\tfile1.ext\n\t\tsubsubdir1\n\tsubdir2\n\t\tsubsubdir2\n\t\t\tfile2.ext"


def lengthLongestPath(string):
  # a stack, each element is a tuple ("dir_name", length of name)
  pwd = []
  prefix_length = 0
  currMax = -1
  # if we see \n means we go into the next directory
  # the number of \t s folllowing \n is the number of elements in pwd we need to keep
  items = string.split("\n")
  for i in items:
    tab_split = i.split("\t")
    # length of tab_split - 1 is the no of elem we want to keep in pwd
    while (len(pwd) > len(tab_split) -1): # remove excess items
      prefix_length -= pwd.pop()[1] # index 1 is the length
    curr_item = tab_split[-1]
    # cannot find dot, is a directory
    if not curr_item.find('.'):
      pwd += (curr_item, len(curr_item))
    else: # current item is a file
      # length of current path = filename_len + prefix_length + no of slashes
      currMax = max(currMax, len(curr_item) + prefix_length + len(pwd))
    return currMax

lengthLongestPath(test_1)