// The "Primes" class.
import java.awt.*;
import java.util.*;
import java.io.*;

public class Primes
{
    public static void main (String [] args) throws IOException
    { // Open up the input and output file for IO purpose
	FileReader inFile = new FileReader ("DATA1.txt");
	FileWriter outFile = new FileWriter ("OUT1.txt");

	// Link the input and output file for
	BufferedReader in = new BufferedReader (inFile);
	BufferedWriter out = new BufferedWriter (outFile);

	String line;

	//V
	int inputnum = 1, resultnum = 1, reminputnum, remdiv = 0, counter = 0;
	float rem;

	String output = "", newoutput = "";

	boolean negnum = false;

	//P && I && O
	while ((line = in.readLine ()) != null)
	{
	    //I
	    inputnum = Integer.parseInt (line);
	    //P
	    if (inputnum == 0)
		break;
	    else if (inputnum < 0)
	    {
		inputnum *= -1;
		negnum = true;
	    }

	    //P
	    reminputnum = inputnum;

	    for (int div = 2 ; reminputnum != resultnum ; div++)
	    {
		rem = inputnum / div;

		if (div * rem == inputnum)
		{
		    if (negnum == true)
			output += (div * -1) + "  ";
		    else
			output += div + " ";

		    inputnum /= div;
		    resultnum *= div;

		    if (reminputnum == resultnum)
			remdiv = div;

		    div = 1;
		    counter++;
		}
	    }

	    if (negnum == true)
	    {
		reminputnum *= -1;

		if (counter % 2 == 0)
		{
		    StringTokenizer token = new StringTokenizer (output);

		    for (int x = 1 ; x != counter ; x++)
			newoutput += token.nextToken () + " ";

		    output = newoutput + remdiv + " ";
		}
	    }

	    //O
	    StringTokenizer token = new StringTokenizer (output, " ");

	    if (token.countTokens () == 3)
	    {
		int num1 = Integer.parseInt(token.nextToken());
		int num2 = Integer.parseInt(token.nextToken());
		int num3 = Integer.parseInt(token.nextToken());

		if (num1 != num2 && num1 != num3 && num2 != num3)
		    out.write("valid");
		else
		    out.write("not");
		out.newLine();
	    }
	    else
	    {
		out.write ("not");
		out.newLine ();
	    }


	    //P
	    output = "";
	    newoutput = "";
	    inputnum = 1;
	    resultnum = 1;
	    reminputnum = 0;
	    remdiv = 0;
	    counter = 0;

	}

	in.close ();
	out.close ();
    } // main method
} // Primes class