Given an absolute path for a file (Unix-style), simplify it. Or in other words, convert it to the canonical path.
In a UNIX-style file system, a period .
refers to the current directory. Furthermore, a double period ..
moves the directory up a level. For more information, see: Absolute path vs relative path in Linux/Unix
Note that the returned canonical path must always begin with a slash /
, and there must be only a single slash /
between two directory names. The last directory name (if it exists) must not end with a trailing /
. Also, the canonical path must be the shorteststring representing the absolute path.
Example 1:
Input: "/home/" Output: "/home" Explanation: Note that there is no trailing slash after the last directory name.
Example 2:
Input: "/../" Output: "/" Explanation: Going one level up from the root directory is a no-op, as the root level is the highest level you can go.
Example 3:
Input: "/home//foo/" Output: "/home/foo" Explanation: In the canonical path, multiple consecutive slashes are replaced by a single one.
Example 4:
Input: "/a/./b/../../c/"
Output: "/c"
题意
遇到"."的情况直接去掉,遇到".."删掉它上面挨着的一个路径, 求简化后的路径
思路
很接近real industry的题目
将input通过/分离出来, 利用Stack来模拟遇到"."和".."的情况
代码
1 public class _71_SimplifyPath { 2 public String simplifyPath(String path) { 3 // corner case 4 if (path.length() <= 1) return path; 5 //split inout 6 String[] input = path.split("/"); 7 Stack<String> stack = new Stack<>(); 8 for (String s : input) { 9 if (s.equals("..")) { 10 if (!stack.empty()) { 11 stack.pop(); 12 } 13 } else if (s.equals(".") && !s.isEmpty()) { 14 stack.push(s); 15 } 16 } 17 String result = " "; 18 if (stack.isEmpty()) return "/"; 19 while (!stack.empty()) { 20 String cur = stack.pop(); 21 result = "/" + cur + result; 22 } 23 return result; 24 } 25 }