71. Simplify Path

Given an absolute path for a file (Unix-style), simplify it.

For example,
path = "/home/", => "/home"
path = "/a/./b/../../c/", => "/c"

题目含义：简化unix路径

    public String simplifyPath(String path) {
        Stack<String > stack = new Stack<>();
        List<String> skip = Arrays.asList("..",".","");
        for (String str:path.split("/"))
        {
            if (str.equals("..") && !stack.isEmpty()) stack.pop();
            else if (!skip.contains(str)) stack.push(str);
        }
        String result="";
        for (String item:stack)
        {
            result +=  "/" + item;
        }
        return result.isEmpty()?"/":result;     
    }