Consider a tic-tac-toe on a 3x3 board. Tic-tac-toe is a two-player battle game. Decide the first attack and the second attack, one hits Kuroishi and one hits Shiraishi. The winner is the person who puts stones one by one on the board alternately and arranges three of his own stones first in either the vertical, horizontal, or diagonal direction.

Create a program that inputs the information on the board, judges the victory or defeat, outputs "b" if black wins, "w" if white wins, and "NA" if neither is available. please. The board information consists of 3 rows and 3 columns of character strings. "B" is Kuroishi, "w" is Shiraishi, and "+" (half-width plus) is nothing. However, three blacks and three whites cannot be lined up at the same time.



Input

A sequence of multiple datasets is given as input. The end of the input is indicated by a single line of zeros. Each dataset is given in the following format:


board1
board2
board3


The i-line is given the string boardi that represents the information on the i-th line of the board.

The number of datasets does not exceed 50.

Output

Outputs "b", "w", or "NA" on one line for each data set.

Example

Input

bbw
wbw
+b+
bwb
wbw
wbw
0


Output

b
NA
import java.util.*;
import java.io.*;

public class Main {

	static void solve (FastScanner in, PrintWriter out, Methods ms) {
		
		while (true) {

			char[][] map = new char[3][3];
			String s = in.next();
			if (s.equals("0")) return;

			map[0] = s.toCharArray();
			map[1] = in.next().toCharArray();
			map[2] = in.next().toCharArray();

			String ans = "NA";
			if (isSame(map[0][0], map[0][1], map[0][2])) ans = String.valueOf(map[0][0]);
			else if (isSame(map[1][0], map[1][1], map[1][2])) ans = String.valueOf(map[1][0]);
			else if (isSame(map[2][0], map[2][1], map[2][2])) ans = String.valueOf(map[2][0]);
			else if (isSame(map[0][0], map[1][0], map[2][0])) ans = String.valueOf(map[0][0]);
			else if (isSame(map[0][1], map[1][1], map[2][1])) ans = String.valueOf(map[0][1]);
			else if (isSame(map[0][2], map[1][2], map[2][2])) ans = String.valueOf(map[0][2]);
			else if (isSame(map[0][0], map[1][1], map[2][2])) ans = String.valueOf(map[0][0]);
			else if (isSame(map[0][2], map[1][1], map[2][0])) ans = String.valueOf(map[0][2]);
			
			out.println(ans);
		}

	}

	static boolean isSame (char a, char b, char c) {
		if (a=='+' || b=='+' || c=='+') return false;
		if (a==b && b==c && a==c) return true;
		else return false;
	}



	public static void main(String[] args) {
		FastScanner in = new FastScanner(System.in);
		PrintWriter out = new PrintWriter(System.out);
		Methods ms = new Methods();
		solve(in, out, ms);
		in.close();
		out.close();
	}

	static class Methods {

		public void print (Object... ar) {System.out.println(Arrays.deepToString(ar));}

		public int max (int... ar) {Arrays.sort(ar); return ar[ar.length-1];}

		public int min (int... ar) {Arrays.sort(ar); return ar[0];}

		public long gcd (long a, long b) {return b>0?gcd(b,a%b):a;}

		public long lcm (long a, long b) {return a/gcd(a,b)*b;}

		public long factorial (int i) {
			if (i==1) return 1;
			else return i*factorial(i-1);
		}

		public int manhat (int x1, int y1, int x2, int y2) {
			return Math.abs(x1-x2)+Math.abs(y1-y2);
		}

		public double euclid (double x1, double y1, double x2, double y2) {
			return Math.sqrt((x2-x1)*(x2-x1)+(y2-y1)*(y2-y1));
		}

		public boolean isPrime (int n) {
			if (n==2) return true;
			if (n<2 || n%2==0) return false;
			for (int i=3; i<=Math.sqrt(n); i+=2) if(n%i==0) return false;
			return true;
		}

	}

	static class FastScanner {

		private InputStream in;
		private byte[] buffer = new byte[1024];
		private  int length = 0, p = 0;

		public FastScanner (InputStream stream) {
			in = stream;
		}

		public boolean hasNextByte () {
			if (p < length) return true;
			else {
				p = 0;
				try {length = in.read(buffer);}
				catch (Exception e) {e.printStackTrace();}
				if (length <= 0) return false;
			}
			return true;
		}

		public int readByte () {
			if (hasNextByte() == true) return buffer[p++];
			return -1;
		}

		public boolean isPrintable (int n) {return 33<=n&&n<=126;}

		public void skip () {
			while (hasNextByte() && !isPrintable(buffer[p])) p++;
		}

		public boolean hasNext () {skip(); return hasNextByte();}

		public String next () {
			if (!hasNext()) throw new NoSuchElementException();
			StringBuilder sb = new StringBuilder();
			int t = readByte();
			while (isPrintable(t)) {
				sb.appendCodePoint(t);
				t = readByte();
			}
			return sb.toString();
		}

		public String[] nextArray (int n) {
			String[] ar = new String[n];
			for (int i=0; i<n; i++) ar[i] = next();
			return ar;
		}

		public int nextInt () {return Math.toIntExact(nextLong());}

		public int[] nextIntArray (int n) {
			int[] ar = new int[n];
			for (int i=0; i<n; i++) ar[i] = nextInt();
			return ar;
		}

		public long nextLong () {
			if (!hasNext()) throw new NoSuchElementException();
			boolean minus = false;
			int temp = readByte();
			if (temp == '-') {
				minus = true;
				temp = readByte();
			}
			if (temp<'0' || '9'<temp) throw new NumberFormatException();
			long n = 0;
			while (isPrintable(temp)) {
				if ('0'<=temp && temp<='9') {
					n *= 10;
					n += temp - '0';
				}
				else throw new NumberFormatException();
				temp = readByte();
			}
			return minus? -n : n;
		}

		public long[] nextLongArray (int n) {
			long[] ar = new long[n];
			for (int i=0; i<n; i++) ar[i] = nextLong();
			return ar;
		}

		public double nextDouble () {
			return Double.parseDouble(next());
		}

		public double[] nextDoubleArray (int n) {
			double[] ar = new double[n];
			for (int i=0; i<n; i++) ar[i] = nextDouble();
			return ar;
		}

		public void close () {
			try {in.close();}
			catch(Exception e){}
		}

	}

}
