Java String Tokens | Regex expression

Given a string, , matching the regular expression [A-Za-z !,?._'@]+, split the string into tokens. We define a token to be one or more consecutive English alphabetic letters. Then, print the number of tokens, followed by each token on a new line.

Note: You may find the String.split method helpful in completing this challenge.

Input Format

A single string, .

Constraints

•  is composed of any of the following: English alphabetic letters, blank spaces, exclamation points (!), commas (,), question marks (?), periods (.), underscores (_), apostrophes ('), and at symbols (@).

Output Format

On the first line, print an integer, , denoting the number of tokens in string  (they do not need to be unique). Next, print each of the  tokens on a new line in the same order as they appear in input string .

Sample Input

He is a very very good boy, isn't he?

Sample Output

10
He
is
a
very
very
good
boy
isn
t
he

Explanation

We consider a token to be a contiguous segment of alphabetic characters. There are a total of  such tokens in string , and each token is printed in the same order in which it appears in string .

import java.io.*;
import java.util.*;

public class Solution {

   public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        String s = scan.nextLine();
        // Write your code here.
       // s = s.replaceAll("\\", "");
        s=s.trim();
        if(s.isEmpty()) {
         System.out.println(0);
        }else {
         
            String[] a = s.split("[ !,?._'@]+");
            System.out.println(a.length);
            s=s.replaceAll("[ !,?._'@]+", "\n");
            System.out.println(s);
            
        }
        scan.close();
        
    }
}