/* 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
	{
		Pattern pattern = Pattern.compile("\\b\\pL+(?:-\\pL+)*\\b", Pattern.UNICODE_CHARACTER_CLASS);
	    Matcher matcher = pattern.matcher("5 * loop-num + 5");
	    if(matcher.find()){
	        String extractedString = matcher.group(0);
	        System.out.println(extractedString);
	    }
	}
}

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