(SPOJ) 2844 - Você pode dizer 11 - Solução

import java.io.*;
import java.util.*;

class Main {
    public static void main(String[] args) throws NumberFormatException, IOException {
        Main processando = new Main();
        processando.processa();
       
        System.exit(0);
    }
   
    void processa() throws NumberFormatException, IOException {
        String line = "";
       
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
       
        while((line = br.readLine()) != null) {
            if (line.length() == 1 && line.charAt(0) == '0') {
                return;
            }
           
            int pares = 0;
            int impares = 0;
            for (int i = 0; i < line.length(); i=i+2) {
                pares += (line.charAt(i)-'0');
            }
            for (int i = 1; i < line.length(); i=i+2) {
                impares += (line.charAt(i)-'0');
            }

            if (((impares+11-pares)%11) != 0) {
                bw.write(line + " is not a multiple of 11.\n");
            }
            else {
                bw.write(line + " is a multiple of 11.\n");
            }
           
            bw.flush();
        }

        bw.close();                   
        return;
    }
}