How to solve it
package com.codegym.task.task19.task1908;
/*
Picking out numbers
*/
import java.io.*;
import java.util.ArrayList;
public class Solution {
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String a = br.readLine();
String b = br.readLine();
br.close();
BufferedReader br1 = new BufferedReader(new FileReader(a));
FileWriter fw = new FileWriter(b);
BufferedWriter bw = new BufferedWriter(fw);
while (br1.ready()) {
String str = br1.readLine();
String good = str.replaceAll("\\D+", " ");
bw.write(good);
}
bw.close();
br1.close();
}
}