/* 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 str = "REPEAT_FOR_4";
        Pattern p = Pattern.compile("([0-9]+)");
        Matcher m = p.matcher(str);
        StringBuffer s = new StringBuffer();
        while (m.find())
            m.appendReplacement(s, String.valueOf(1+ Integer.parseInt(m.group(1))));
        System.out.println(s.toString());
	}
}

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