Simplify Path

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

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

思路

以/为分界符split，如/a/./b/../../c/，分成a,.,b,..,..,c这样，将a，b..依次入栈，如果，是..出栈，最后从栈底遍历到栈底为最后的路径。因为最后要从栈底遍历到栈顶，我用的是list不是stack

import java.util.ArrayList;
import java.util.List;

public class Solution {
    public String simplifyPath(String path) {
        List<String> stack = new ArrayList<String>();            //这里的List有stack的作用
        String result = "";
        
        int ptrOfPath = 1;
        String element = "";
        while(ptrOfPath < path.length() && path.charAt(ptrOfPath) == '/')
            ptrOfPath++;
        while(ptrOfPath < path.length() && path.charAt(ptrOfPath) != '/'){
            element += path.charAt(ptrOfPath);
            ptrOfPath++;
        }//while
        ptrOfPath ++;
        if(!element.equals(".") && !element.equals("..") && !element.equals("/"))
            stack.add(element);
        element = "";
        boolean startNewWord = false;
        while(ptrOfPath < path.length()){
            if(startNewWord == true)
            {
                element = "";
                startNewWord = false;
            }
            if(path.charAt(ptrOfPath) == '/' || ptrOfPath == path.length() - 1){
                startNewWord = true;
                if(ptrOfPath == path.length() - 1 && path.charAt(ptrOfPath) != '/')
                    element += path.charAt(ptrOfPath);
                if(element.length() != 0 && element.equals("..")){
                    if(stack.size() != 0)
                        stack.remove(stack.size() - 1);                //出栈
                }
                else if(element.length() != 0 && !element.equals(".")){
                    stack.add(element);                                //入栈
                }
                ptrOfPath++;
                continue;
            }//if
            else{
                element += path.charAt(ptrOfPath ++);
            }
        }//while
        if(stack.size() == 0)
            return "/";
        //遍历list获取结果
        for(String str : stack){
            result += "/";
            result += str;
        }//for
        
        return result;
    }
}