(SPOJ) 8697 - Pneu - Solução 2

import java.io.*;
import java.util.*;
import java.lang.Math;
import java.math.*;

class Main {
    public static void main(String[] args) throws NumberFormatException, IOException {
        Main processando = new Main();
        processando.processa();
       
        System.exit(0);
    }
   
    static int leitor(BufferedReader br) throws NumberFormatException, IOException {
        int n;
        int 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));
       
        int valor1 = leitor(br);

        int valor2 = leitor(br);
                   
        System.out.println(valor1-valor2);
           
        return;
    }
}