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.
import java.io.*;

public final class VityaCountryside{

	public static void main(String args[]) throws Exception{

		int N = Br.getInt();

		String temp[] = Br.getString().split(" ");

		int a = Integer.parseInt(temp[N-1]);

		if(a == 15)
			println("DOWN");
		else if(a == 0)
			println("UP");
		else{

			if(N == 1)
				println("-1");
			else{

				int b = Integer.parseInt(temp[N-2]);
				if(a-b == 1)
					println("UP");
				else
					println("DOWN");
			}
		}
	}

	// class for Reader
	static class Br {

		final static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

		static int getInt() throws IOException{
			return Integer.parseInt(br.readLine());
		}

		static long getLong() throws IOException{
			return Long.parseLong(br.readLine());
		}

		static double getDouble() throws IOException{
			return Double.parseDouble(br.readLine());
		}

		static int[] getIntA() throws IOException{
			String temp[] = br.readLine().split(" ");
			int l = temp.length;

			int a[] = new int[l];

			for(int i=0; i<l; i++){
				a[i] = Integer.parseInt(temp[i]);
			}

			return a;
		}

		static int[] getIntA(int l) throws IOException{
			String temp[] = br.readLine().split(" ");
			int a[] = new int[l];

			for(int i=0; i<l; i++){
				a[i] = Integer.parseInt(temp[i]);
			}

			return a;
		}

		static long[] getLongA(int l) throws IOException{
			String temp[] = br.readLine().split(" ");
			long a[] = new long[l];

			for(int i=0; i<l; i++){
				a[i] = Long.parseLong(temp[i]);
			}

			return a;
		}

		static String getString() throws IOException{
			return br.readLine();
		}

	}

	// class for MaTh libraries
	static class Mt{
		static double precision = 0.00001;

		static double sqrt(double a){
			return newton_raphson(a, a/2);
		}

		static double newton_raphson(double a, double guess){
			if(guess*guess - a <= precision)
				return guess;

			guess = guess - (guess * guess - a)/ (2 * guess);
			return newton_raphson(a, guess);
		}
	}

	static<T> void print(T s){
		System.out.print(s);
	}

	static<T> void println(T s){
		System.out.println(s);
	}
}