[LeetCode]Simplify Path

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

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

click to show corner cases.

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".

public class Solution {    public String simplifyPath(String path) {    Stack<String> stack = new Stack<>();         for(int i=0;i<path.length();){        int j = path.indexOf("/",i);        if(j==-1){        String s = path.substring(i,path.length());        if(!s.equals(".")&&!s.equals("..")){        stack.push(s);        }        if(s.equals("..")&&!stack.isEmpty()) stack.pop();        break;        }        if(i==j){        i++;        continue;        }        String str = path.substring(i, j);        if(!str.equals(".")){        if(str.equals("..")){        if(!stack.isEmpty()) stack.pop();        }else{        stack.push(str);        }        }        i=j;        }        if(stack.isEmpty()) return "/";        StringBuilder sb = new StringBuilder();        while(!stack.isEmpty()){        sb.insert(0, "/"+stack.pop());        }        return sb.toString();    }}