AC代码：
import java.util.Scanner;
/**
* @author CC11001100
*/
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNextLine()){
System.out.println(decode(sc.nextLine()));
}
}
private static String decode(String s){
StringBuilder res = new StringBuilder();
for(int i=0; i<s.length(); i++){
char c = s.charAt(i);
if(Character.isDigit(c)){
res.append(c);
}
}
return res.toString();
}
}