/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.util.regex.*;
/* 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 s = "CX12345\nCX14584\nJB145888\nJD748452\nCX12345\nLM45855";
		String p = "(?s)\\b((?!CR|cr)[A-Za-z]{2}\\d{5,6})\\b(?!.*\\b\\1\\b)";
		Pattern pattern = Pattern.compile(p);
		Matcher matcher = pattern.matcher(s);
		while (matcher.find()){
			System.out.println(matcher.group(0)); 
		} 
	}
}

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