import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner scanner = new Scanner(System.in); String str = scanner.next(); String emailMatcher="[a-zA-Z0-9]+@[a-zA-Z0-9]+\\.[a-zA-Z0-9]+"; //write your code here...... // boolean matches(String regex): // matches() 方法用于检测字符串是否匹配给定的正则表达式 if (str.matches(emailMatcher)){ System.out.println("邮箱格式合法"); } else { System.out.println("邮箱格式不合法"); } } }