FileSystem

import java.util.*;

class MyRunnableThread implements Runnable{
	 
    public  String value ;
    public MyRunnableThread(String value){
         this.value=value;
    }
    public void run() {
    	System.out.println(value);
    } 
}
public class FileSystem {
	Map<String,Integer> fileMap;
	Map<String, Runnable> callBackMap;
	public FileSystem() {
		this.fileMap = new HashMap<>();
		this.callBackMap = new HashMap<>();
		this.fileMap.put("", 0);
	}
	public boolean create(String filePath,int value) {
		if(fileMap.containsKey(filePath)) return false;
		int lastSlashIndex = filePath.lastIndexOf("/");
		if(!fileMap.containsKey(filePath.substring(0, lastSlashIndex))) return false;
		fileMap.put(filePath, value);
		return true;
	}
	
	public int get(String filePath) {
		if(fileMap.containsKey(filePath)) return fileMap.get(filePath);
		return -1;
	}
	
	public boolean set(String filePath, int value) {
		if(!fileMap.containsKey(filePath)) return false;
		fileMap.put(filePath, value);
		String curPath = filePath;
		while(curPath.length()>0) {
			if(callBackMap.containsKey(curPath)) {
				callBackMap.get(curPath).run();
			}
			int lastSlashIndex = filePath.lastIndexOf("/");
			curPath = filePath.substring(0, lastSlashIndex);
		}
		return  true;
	}
	
	public boolean watch(String filePath,Runnable callback) {
		if(!fileMap.containsKey(filePath)) return false;
		callBackMap.put(filePath, callback);
		return true;
	}
	
	public static void main(String []args) {
		FileSystem fs = new FileSystem();
		fs.create("/a", 1);
		System.out.println(fs.get("/a"));
		fs.create("/a/b", 2);
		System.out.println(fs.get("/a/b"));
		fs.create("/c/d", 1);
		System.out.println(fs.get("/c"));
		
	
		
		fs.watch("/a",new MyRunnableThread("yes"));
		fs.watch("/a/b",new MyRunnableThread("no"));
		fs.set("/a", 1);
		fs.set("/a/b", 2);
		fs.create("/a/b/c", 1);
		
	}
}