Every summer Vitya comes to visit his grandmother in the countryside. This summer, he got a huge wart. Every grandma knows that one should treat warts when the moon goes down. Thus, Vitya has to catch the moment when the moon is down.

Moon cycle lasts 30 days. The size of the visible part of the moon (in Vitya's units) for each day is 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, and then cycle repeats, thus after the second 1 again goes 0.

As there is no internet in the countryside, Vitya has been watching the moon for n consecutive days and for each of these days he wrote down the size of the visible part of the moon. Help him find out whether the moon will be up or down next day, or this cannot be determined by the data he has.

Input

The first line of the input contains a single integer n (1 ≤ n ≤ 92) — the number of consecutive days Vitya was watching the size of the visible part of the moon. 

The second line contains n integers ai (0 ≤ ai ≤ 15) — Vitya's records.

It's guaranteed that the input data is consistent.

Output

If Vitya can be sure that the size of visible part of the moon on day n + 1 will be less than the size of the visible part on day n, then print "DOWN" at the only line of the output. If he might be sure that the size of the visible part will increase, then print "UP". If it's impossible to determine what exactly will happen with the moon, print -1.

Examples

Input

5
3 4 5 6 7


Output

UP


Input

7
12 13 14 15 14 13 12


Output

DOWN


Input

1
8


Output

-1

Note

In the first sample, the size of the moon on the next day will be equal to 8, thus the answer is "UP".

In the second sample, the size of the moon on the next day will be 11, thus the answer is "DOWN".

In the third sample, there is no way to determine whether the size of the moon on the next day will be 7 or 9, thus the answer is -1.
//719A : VITYA IN THE COUTNRYSIDE

/*

 * Solution: 
 */

/*
 * Prerequisite:
 * 	- Logical Reasoning
 */
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.StringTokenizer;

//Your code goes here
public class Main {	
	
	static class ProblemSolver{
		public void solveTheProblem(InputReader in,PrintWriter out){
			/*
			 * Declare the variables
			 * Take the necessary inputs 
			 * Compute the result along with the other steps 
			 */
			int n=in.nextInt();
			/*
			 * If the number of inputs is 1 then the result
			 * is determinable if and only if the input is 
			 * 15 or 0 as after the 15th day the moon has to 
			 * reduce its size and after the 0th day it has to
			 * increase its size. And for others it is not possible
			 * Ex: if it is the case of 8th day then it could be 
			 *     successor of either 7 or 9.
			 */
			if(n==1){
				int temp=in.nextInt();
				if(temp==0)System.out.println("UP");
				else if(temp==15)System.out.println("DOWN");
				else System.out.println("-1");
				return;
			}
			/*
			 * In the loop we simply need to take care of one
			 * condition that is the previously scanned variable
			 * must be either one greater or one less than the
			 * current scanned variable.
			 */
			int current,previous,_previous;
			current=in.nextInt();
			previous=current;
			_previous=previous;
			--n;
			while(n-->0){
				current=in.nextInt();
				if(current==(_previous-1)||current==(_previous+1)){
					previous=_previous;
					_previous=current;					
				}else{
					System.out.println("-1");
					return;
				}
			}
			/*
			 * After the loop we need to take care of the exception 
			 * that if the current value is 15 then the size will
			 * decrease and if it 0 then the size will increase.
			 * 
			 * And for the other cases it is obvious that if the 
			 * previous is less than the current then the moon is 
			 * in increasing stage and vice versa.
			 * Ex: previous = 13 and current = 	14 then the next
			 *     would be 15.
			 */
			if(current==15)System.out.println("DOWN");
			else if(current==0)System.out.println("UP");
			else if(previous<current)System.out.println("UP");
			else if(previous>current)System.out.println("DOWN");
			
		}					
	}
	
	//Default template for all the codes
	static class InputReader {
        public BufferedReader reader;
        public StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream),32768);
            tokenizer = null;
        }

        public String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        public int nextInt() {
            return Integer.parseInt(next());
        }

    }
	
	//Main method for all the codes
	public static void main(String[] args) {
		InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
		ProblemSolver problemSolver = new ProblemSolver();
		problemSolver.solveTheProblem(in, out);		
		out.close();		
	}

}