/* 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 s = "msqlsum81pv 0 0 25 25 25 2  -sn D:\\workdir\\PV 81\\config\\sum81pv.pwf -C 5000";
		Pattern pattern = Pattern.compile("\\s-s?n\\s*(.*?)\\s*-C\\s+\\d+$");
		Matcher matcher = pattern.matcher(s);
	 	if (matcher.find()){
			System.out.println(matcher.group(1)); 
		} 
	}
}

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