Simplify Path


Given an absolute path for a file (Unix-style), simplify it.
For example,
path = "/home/", => "/home"
path = "/a/./b/../../c/", => "/c"
Corner Cases:
  • Did you consider the case where path = "/../"?
    In this case, you should return "/".
  • Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".
    In this case, you should ignore redundant slashes and return "/home/foo".
Solution: Use stack to deal with "..". I use the approach in section 7.3 of this page to split the string into tokens for given delimiter.

Another approach is to first copy the string into a c_str, then use strtok.
Or we can directly traverse through the string and check the delimiter. There is no essential difference.

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