【LeetCode】Simplify Path 解题报告

【题目】

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".

【解析】

题意：简化Unix下的文件路径，包括多余斜杠的去除，当前目录（./）的去除，以及父目录（../）的替代。

题目给的Tags是栈，但我觉得用个队列更方便些，这样简化后的目录就不用倒着生成了。

【Java代码】

public class Solution {
    public String simplifyPath(String path) {
        LinkedList<String> queue = new LinkedList<String>();
        String[] names = path.split("/");

        for (int i = 0; i < names.length; i++) {
            if ("".equals(names[i]) || ".".equals(names[i])) continue;

            if ("..".equals(names[i])) {
                if (!queue.isEmpty()) {
                    queue.pollLast();
                }
            } else {
                queue.add(names[i]);
            }
        }

        StringBuilder newPath = new StringBuilder();
        while (!queue.isEmpty()) {
            newPath.append("/");
            newPath.append(queue.pollFirst());
        }

        if (newPath.length() == 0) return "/";

        return newPath.toString();
    }
}