609. Find Duplicate File in System

609. Find Duplicate File in System

题目描述：Given a list of directory info including directory path, and all the files with contents in this directory, you need to find out all the groups of duplicate files in the file system in terms of their paths.

A group of duplicate files consists of at least two files that have exactly the same content.

A single directory info string in the input list has the following format:

"root/d1/d2/.../dm f1.txt(f1_content) f2.txt(f2_content) ... fn.txt(fn_content)"

It means there are n files (

f1.txt

,

f2.txt

…

fn.txt

with content

f1_content

,

f2_content

…

fn_content

, respectively) in directory

root/d1/d2/.../dm

. Note that n >= 1 and m >= 0. If m = 0, it means the directory is just the root directory.

The output is a list of group of duplicate file paths. For each group, it contains all the file paths of the files that have the same content. A file path is a string that has the following format:

"directory_path/file_name.txt"

Example 1:

Input:
["root/a 1.txt(abcd) 2.txt(efgh)", "root/c 3.txt(abcd)", "root/c/d 4.txt(efgh)", "root 4.txt(efgh)"]
Output:
[["root/a/2.txt","root/c/d/4.txt","root/4.txt"],["root/a/1.txt","root/c/3.txt"]]

题目大意：找出包含相似内容的文件

思路：使用hashmap

代码

package String;

import java.util.*;

/**
* @Author OovEver
* @Date 2017/12/10 23:32
*/
public class LeetCode609 {
public static List<List<String>> findDuplicate(String[] paths) {
List<List<String>> res = new ArrayList<>();
if (paths == null || paths.length == 0) {
return res;
}
int n = paths.length;
//        map的key存储content即文件内容
//        map的value存储包含当前文件的文件夹
Map<String, Set<String>> map = new HashMap<>();
for (S
4000
tring path : paths) {
//            过滤一个或者多个空格
String[] strs = path.split("\\s+");
for(int i=1;i<strs.length;i++) {
int idx = strs[i].indexOf("(");
String content = strs[i].substring(idx);
String filename = strs[0] + "/" + strs[i].substring(0, idx);
Set<String> filenames = map.getOrDefault(content, new HashSet<String>());
filenames.add(filename);
map.put(content, filenames);
}
}
for (String key : map.keySet()) {
if (map.get(key).size() > 1) {
res.add(new ArrayList<String>(map.get(key)));
}
}
return res;
}

public static void main(String[] args) {
String[] paths = {"root/a 1.txt(abcd) 2.txt(efgh)", "root/c 3.txt(abcd)", "root/c/d 4.txt(efgh)", "root 4.txt(efgh)"};
Set<Integer> set = new HashSet<>();
set.add(1);
set.add(1);
System.out.println(findDuplicate(paths));
}
}