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......
scanner.close();
//可以利用matches()方法进行正则匹配
System.out.println(str.matches(emailMatcher) ? "邮箱格式合法" : "邮箱格式不合法");
}
}

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