вроде разобрался немного в regex, но не проходит
package com.javarush.task.task19.task1908;
import java.io.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/*
Выделяем числа
*/
public class Solution {
public static void main(String[] args) {
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
BufferedReader filereader = new BufferedReader(new FileReader(reader.readLine()));
BufferedWriter filewriter = new BufferedWriter(new FileWriter(reader.readLine()));
reader.close();
String line;
while((line=filereader.readLine())!=null) {
Pattern p = Pattern.compile("\\s\\d+\\s");
Matcher m = p.matcher(line);
while(m.find()) {
filewriter.write(m.group().substring(1));
}
filewriter.newLine();
}
filewriter.close();
filereader.close();
}catch(IOException e) {e.printStackTrace();}
}
}