LeetCode

题目：

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

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

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".

思路：

线分割，然后在stack里进行操作

package ds;

import java.util.Stack;

public class SimplifyPath {

    public String simplifyPath(String path) {
        String[] names = path.split("/");
        Stack<String> s = new Stack<String>();
        for (int i = 0; i < names.length; ++i) {
            String name = names[i];
            switch (name) {
                case "":
                case ".":
                    break;
                case "..":
                    if (!s.isEmpty()) s.pop();
                    break;
                default:
                    s.push(name);
                    break;
            }
        }
        
        if (s.isEmpty()) return "/";
        StringBuilder res = new StringBuilder();
        while (!s.isEmpty()) {
            res.insert(0, "/" + s.pop());
        }
        
        return res.toString();
    }
    
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String path = "/a/b/c////d/e/";
        SimplifyPath s = new SimplifyPath();
        System.out.println(s.simplifyPath(path));
    }

}