import java.util.Scanner;

public class Main{
    public static void main(String[] args){
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    }
} import java.util.Scanner; Scanner java.util public class Main{
    public static void main(String[] args){
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    }
} Main public static void main(String[] args){
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    } main {
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    } int sum=0 sum 0 i=0 i 0 j; j String t; t Scanner s = new Scanner(System.in); s new Scanner(System.in) while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        } true {
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        } t = s.next() t s.next() s.next s if(t.charAt(0) =='0'&&t.length()==1)break; t.charAt(0) =='0'&&t.length()==1 t.charAt(0) =='0' t.charAt(0) t.charAt t 0 '0' t.length()==1 t.length() t.length t 1 break; for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            } i=0; i=0 i 0 i<t.length() i t.length() t.length t i++ i++ i {
                sum+=t.charAt(i)-'0';
            } {
                sum+=t.charAt(i)-'0';
            } sum+=t.charAt(i)-'0' sum t.charAt(i)-'0' t.charAt(i) t.charAt t i '0' System.out.println(sum) System.out.println System.out System System.out sum sum = 0 sum 0 String[] args args public class Main{
    public static void main(String[] args){
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    }
} public class Main{
    public static void main(String[] args){
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    }
} Main
import java.util.Scanner;

public class Main{
    public static void main(String[] args){
        int sum=0,i=0,j;
        String t;
        Scanner s = new Scanner(System.in);
        while(true){
            t = s.next();
            if(t.charAt(0) =='0'&&t.length()==1)break;
            for(i=0;i<t.length();i++){
                sum+=t.charAt(i)-'0';
            }
            System.out.println(sum);
            sum = 0;
        }
    }
}
