[20260129] BOJ / G3 / 폴더 정리 (small) / 이인희

Author: LiiNi-coder

LiiNi-coder/202601/29 BOJ 폴더 정리 (small).md

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+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+public class Main{
+	static class Folder{
+		String name;
+		Set<Folder> folders;
+		Set<String> files;
+		Map<String, Integer> lowerFileCountAtName;
+		Folder(String name){
+			this.name = name;
+			folders = new HashSet<>();
+			files = new HashSet<>();
+		}
+		void addFolder(Folder target){
+			this.folders.add(target);
+		}
+		void addFile(String fileName){
+			this.files.add(fileName);
+		}
+		Map<String, Integer> getLowerFileCount(){
+			if(lowerFileCountAtName == null){
+				this.lowerFileCountAtName = new HashMap<>();
+				//해당 폴더의 파일 취합
+				Iterator<String> iterFile = files.iterator();
+				while(iterFile.hasNext()){
+					String fileName = iterFile.next();
+					lowerFileCountAtName.put(fileName, lowerFileCountAtName.getOrDefault(fileName, 0) + 1);
+				}
+
+				//dfs로 가장 안쪽까지 가서 해당 폴더의 lowerFileCountAtName을 구함
+				Iterator<Folder> iter = folders.iterator();
+				while(iter.hasNext()){
+					Folder childFolder = iter.next();
+					Map<String, Integer> lfcOfChildFolder = childFolder.getLowerFileCount();
+					for(Map.Entry<String, Integer> entry : lfcOfChildFolder.entrySet()){
+						lowerFileCountAtName.put(entry.getKey(), lowerFileCountAtName.getOrDefault(entry.getKey(), 0) + entry.getValue());
+					}
+				}
+			}
+
+			return lowerFileCountAtName;
+		}
+	}
+	private static int N, M, Q;
+	private static Map<String, Folder> FolderAtName;
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		FolderAtName = new HashMap<>();
+		try{
+			createFolder("main");
+		}catch(NullPointerException e){
+			throw new RuntimeException("createFolder 에러");
+		}
+		String[] tokens = br.readLine().split(" ");
+		N = Integer.parseInt(tokens[0]);
+		M = Integer.parseInt(tokens[1]);
+
+		for(int i = 0; i<N+M; i++){
+			tokens = br.readLine().split(" ");
+			String srcName = tokens[0];
+			Folder src = FolderAtName.get(srcName);
+			if(src == null){
+				src = createFolder(srcName);
+			}
+			String targetName = tokens[1];
+			if("1".equals(tokens[2])){
+				//폴더
+				src.addFolder(createFolder(targetName));
+			}else{
+				//파일
+				src.addFile(targetName);
+			}
+		}
+		Q = Integer.parseInt(br.readLine());
+		int q = Q;
+		while(q-->0){
+			tokens = br.readLine().split("/");
+			Folder target = FolderAtName.get(tokens[tokens.length-1]);
+			Map<String, Integer> temp = target.getLowerFileCount();
+			int answer = 0;
+			for(int c : temp.values()){
+				answer += c;
+			}
+			System.out.println(temp.size() + " " + answer);
+		}
+		br.close();
+	}
+
+	private static Folder createFolder(String name) {
+		FolderAtName.putIfAbsent(name, new Folder(name));
+		return FolderAtName.get(name);
+	}
+}
+```