import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    }
} import java.util.*; util.* java public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    } main {
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        } true {

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        } String x = sc.next(); x sc.next() sc.next sc int ans=0; ans 0 if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            } x.equals("0") x.equals x "0" {break;} break; {
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            } for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                } int i=0; int i=0; i 0 i<x.length() i x.length() x.length x i++ i++ i {
                    ans += (x.charAt(i)-'0');
                } {
                    ans += (x.charAt(i)-'0');
                } ans += (x.charAt(i)-'0') ans (x.charAt(i)-'0') x.charAt(i) x.charAt x i '0' System.out.println(ans) System.out.println System.out System System.out ans ans = 0 ans 0 String[] args args public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    }
} public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    }
} Main
import java.util.*;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        while(true){

            String x = sc.next();
            int ans=0;

            if(x.equals("0")){break;}
            else{
                for(int i=0;i<x.length();i++){
                    ans += (x.charAt(i)-'0');
                }
                System.out.println(ans);
                ans = 0;
            }
        }
    }
}
