(SPOJ) 19941 - Corrida - 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);
    }
   
    static long leitor(BufferedReader br) throws NumberFormatException, IOException {
        long n;
        long resp = 0;
        
        while (true) {
            n = br.read();
            if (n >= '0' && n <= '9') break;
        }
        while (true) {
            resp = resp*10 + n-'0';
            n = br.read();
            if (n < '0' || n > '9') break;
        }
        
        return resp;
    
    }
   
    void processa() throws NumberFormatException, IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
       
        System.out.println(leitor(br)%leitor(br));
                                      
        return;
    }
}