String: 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 "/".
  • In this case, you should ignore redundant slashes and return "/home/foo".
• Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".

public class Solution { public String simplifyPath(String path) { if(path.length() == 0 || path == null) return path; String[] tokens = path.split("/"); Stack<String> stack = new Stack<String>(); for(int i = 0 ; i < tokens.length ; i++){ if(tokens[i].equals("..")){ if(!stack.isEmpty()){ stack.pop(); } else{ continue; } } else if(tokens[i].equals(".")|| tokens[i].length() == 0){ continue; } else{ stack.push(tokens[i]); } } String ret = new String(""); if(stack.isEmpty()) return "/"; Stack<String> stack2 = new Stack<String>(); while(!stack.isEmpty()){ stack2.push(stack.pop()); } while(!stack2.isEmpty()){ ret += "/"; ret += stack2.pop(); } return ret; } }