LintCode 简化路径题目分析代码

public class Solution {
    /**
     * @param path the original path
     * @return the simplified path
     */
    public String simplifyPath(String path) {
        Deque<String> queue = new LinkedList<String>();
        Set<String> skip = new HashSet<String>(Arrays.asList("..",".",""));
        
        for(String dir : path.split("/")) {
            if(dir.equals("..") && !queue.isEmpty()) 
                queue.pop();
            else if(!skip.contains(dir))
                queue.push(dir);
        }
        
        String res = "";
        for(String dir : queue)
            res = "/" + dir + res;
        
        return res.isEmpty() ? "/" : res;
    }
}