import java.io.*;

class Main {
    public static void main(String[] arg)throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while(true){
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        }
    }
} import java.io.*; io.* java class Main {
    public static void main(String[] arg)throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while(true){
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        }
    }
} Main public static void main(String[] arg)throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while(true){
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        }
    } main {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while(true){
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        }
    } BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); br new BufferedReader(new InputStreamReader(System.in)) while(true){
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        } true {
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        } String str = br.readLine(); str br.readLine() br.readLine br if(str.equals("0"))break; str.equals("0") str.equals str "0" break; int sum = 0; sum 0 for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            } int i=0; int i=0; i 0 i<str.length() i str.length() str.length str i++ i++ i {
                sum = sum + Integer.parseInt("" +str.charAt(i));
            } {
                sum = sum + Integer.parseInt("" +str.charAt(i));
            } sum = sum + Integer.parseInt("" +str.charAt(i)) sum sum + Integer.parseInt("" +str.charAt(i)) sum Integer.parseInt("" +str.charAt(i)) Integer.parseInt Integer "" +str.charAt(i) "" str.charAt(i) str.charAt str i System.out.println(sum) System.out.println System.out System System.out sum String[] arg arg
import java.io.*;

class Main {
    public static void main(String[] arg)throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        while(true){
            String str = br.readLine();
            if(str.equals("0"))break;
            int sum = 0;
            for(int i=0;i<str.length();i++){
                sum = sum + Integer.parseInt("" +str.charAt(i));
            }
            System.out.println(sum);
        }
    }
}