/* 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 input = "3.4 5.6 3.400000";
	  input = input.replaceAll("(\\d+)\\.(\\d+)", "$1xx$2");
	  System.out.println(input);
 
	  String two = "3.4 5.6 3.400000";
	  two = two.replaceAll("(?<=\\d)\\.(?=\\d)", "xx");
	  System.out.println(two);
	}
}

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