https://www.acmicpc.net/problem/10952
import java.util.Scanner;
public class Main {
public static void main(String args[]) {
Scanner in = new Scanner(System.in);
while (true) {
int A = in.nextInt();
int B = in.nextInt();
if (A == 0 && B == 0) {
in.close();
break;
}
System.out.println(A + B);
}
}
}