/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
 
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String regex = "^[A-Za-z]{4} \\d{4}$";
		// True
        System.out.println("abcd	1234".matches(regex));
        System.out.println("ABCD 1234".matches(regex));
 
        // False
        System.out.println("AABCD 1234".matches(regex));
        System.out.println("ABCD    1234".matches(regex));
        System.out.println("ABCD 234".matches(regex));
	}
}

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