/* 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 str = "BCTC27452ASDFCCC";
		System.out.println(str.replaceAll("[^A-Z0-9]",""));
		System.out.println(str.replaceAll("[^A-Z0-9]$",""));
		System.out.println(str.replaceAll("[^A-Z][^0-9]",""));
		System.out.println(str.replaceAll("[^A-Z][^0-9]+","")); 	//Why the 2nd '2' isn't getting printed.
		System.out.println(str.replaceAll("[^A-Z][^0-9]*",""));
		System.out.println(str.replaceAll("[^A-Z][^0-9+]",""));
		System.out.println(str.replaceAll("[^A-Z][^0-9*]",""));
 
		System.out.println("Expected Output: BTC27452");
	}
}

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