/* package whatever; // don't place package name! */
 
import java.util.*;
import java.lang.*;
import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
 
/* 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 encoded = "BzM=";
		int scale = 2;
		final BigDecimal decoded = new BigDecimal(new BigInteger(Base64.getDecoder().decode(encoded)), scale);
		System.out.println("RES: " + decoded); // RES: 18.43
	}
}

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