Java for LeetCode 071 Simplify Path

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

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

解题思路：

首先要了解linux目录的意思，请参考Linux的文件管理

先把path按" /" split，建立一个栈，如果出现..则出栈，否则入栈，最后输出这个栈即可，JAVA实现如下：

    public String simplifyPath(String path) {
        Stack<String> res = new Stack<String>();
        String[] ps = path.split("/");
        for (String a : ps) {
            if (a.equals("..")) {
                if (!res.empty())
                    res.pop();
            }
            else if (a.equals(".") || a.equals(""))
                continue;
            else
                res.push(a);
        }
        if (res.empty())
            return "/";
        StringBuilder sb = new StringBuilder();
        while(!res.empty())
        	sb.append("/" + res.get(i));
        return sb.toString();
    }