Puede convertir esta fórmula
2 + 22 + 222 + 2222 = 2 4 = 20 3 + 200 2 + 2000 1
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner scan = new Scanner(System.in);
int count =0;
int num = scan.nextInt();
int flag = scan.nextInt();
while(true) {
count+=num*flag;
num = num*10;
flag--;
if(flag ==0) {
break;
}
}
System.out.println(count);
}
}