(SPOJ) 20002 - Vestibular - 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 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));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));

        int qteQuestoes = leitor(br);
       
        char[] gabarito = new char[qteQuestoes];

        String line = "";
        line = br.readLine();
        for (int i = 0; i < qteQuestoes; i++) {
            gabarito[i] = line.charAt(i);
        }

        int contaCertas = 0;
        line = br.readLine();
        for (int i = 0; i < qteQuestoes; i++) {
            if (line.charAt(i) == gabarito[i]) {
                contaCertas++;
            }
        }

        bw.write(contaCertas + "\n");

        bw.flush();
        bw.close();          

        return;
    }
}