(SPOJ) 20671 - Senha da Tia - 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 minCaracteres = leitor(br);
        int minMinusculas = leitor(br);
        int minMaiusculas = leitor(br);
        int minNumeros = leitor(br);
       
        String senha = br.readLine();

        int contaMinusculas = 0;
        int contaMaiusculas = 0;
        int contaNumeros = 0;
       
        int comprimento = senha.length();
       
        if (comprimento >= minCaracteres) {
            for (int i = 0; i < comprimento; i++) {
                int valor = senha.charAt(i)-'0';
                if (valor >= 0 && valor <= 9) {
                    contaNumeros++;
                }
                else if (valor >= 17 && valor <= 42) {
                    contaMaiusculas++;
                }
                else if (valor >= 49 && valor <= 74) {
                    contaMinusculas++;
                }
            }
           
            if (contaNumeros >= minNumeros && contaMaiusculas >= minMaiusculas && contaMinusculas >= minMinusculas) {
                bw.write("Ok =/\n");
            }
            else {
                bw.write("Ufa :)\n");
            }
        }
        else {
            bw.write("Ufa :)\n");
        }
                   
        bw.flush();
        bw.close();           
        return;
    }
}