import java.util.*; import java.util.regex.*; // 注意类名必须为 Main, 不要有任何 package xxx 信息 public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); String line = in.nextLine(); // regex int countLetter = line.length() - line.replaceAll("[a-zA-Z]", "&q...