/* package whatever; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		String str = "ab message1ab message2ab message3";
		String[] res =str.split("(?!^)\\s*(?=ab)");
		for (String s: res) {
		    System.out.println(s);
		}
}
		
}