import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    }
} import java.io.BufferedReader; BufferedReader java.io import java.io.IOException; IOException java.io import java.io.InputStreamReader; InputStreamReader java.io public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    }
} Main public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    } main {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    } BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        } true {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        } int sum=0; sum 0 String s=br.readLine(); s br.readLine() br.readLine br if(s.equals("0")){
                break;
            } s.equals("0") s.equals s "0" {
                break;
            } break; for (int c : s.toCharArray()) {
                sum+=c-48;
            } int c s.toCharArray() s.toCharArray s {
                sum+=c-48;
            } {
                sum+=c-48;
            } sum+=c-48 sum c-48 c 48 System.out.println(sum) System.out.println System.out System System.out sum String[] args args public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    }
} public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    }
} Main
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main {

    public static void main(String[] args) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while (true) {
            int sum=0;
            String s=br.readLine();
            if(s.equals("0")){
                break;
            }
            for (int c : s.toCharArray()) {
                sum+=c-48;
            }
            System.out.println(sum);

        }
    }
}