Problem: Overlooking the captivating blend of myriads of vernal hues, Arkady the painter lays out a long, long canvas.

Arkady has a sufficiently large amount of paint of three colours: cyan, magenta, and yellow. On the one-dimensional canvas split into n consecutive segments, each segment needs to be painted in one of the colours.

Arkady has already painted some (possibly none or all) segments and passes the paintbrush to you. You are to determine whether there are at least two ways of colouring all the unpainted segments so that no two adjacent segments are of the same colour. Two ways are considered different if and only if a segment is painted in different colours in them.

Input

The first line contains a single positive integer n (1 ≤ n ≤ 100) — the length of the canvas.

The second line contains a string s of n characters, the i-th of which is either 'C' (denoting a segment painted in cyan), 'M' (denoting one painted in magenta), 'Y' (one painted in yellow), or '?' (an unpainted one).

Output

If there are at least two different ways of painting, output "Yes"; otherwise output "No" (both without quotes).

You can print each character in any case (upper or lower).

Examples

Input

5
CY??Y


Output

Yes


Input

5
C?C?Y


Output

Yes


Input

5
?CYC?


Output

Yes


Input

5
C??MM


Output

No


Input

3
MMY


Output

No

Note

For the first example, there are exactly two different ways of colouring: CYCMY and CYMCY.

For the second example, there are also exactly two different ways of colouring: CMCMY and CYCMY.

For the third example, there are four ways of colouring: MCYCM, MCYCY, YCYCM, and YCYCY.

For the fourth example, no matter how the unpainted segments are coloured, the existing magenta segments will prevent the painting from satisfying the requirements. The similar is true for the fifth example.

Solution (in JAVA):

Solution:
import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.math.RoundingMode;
import java.util.*;
import java.util.Map.Entry;

public class Main
{
	private InputStream stream;
	private byte[] buf = new byte[1024];
	private int curChar;
	private int numChars;
	private SpaceCharFilter filter;
	private PrintWriter pw;
	private long mod = 1000000000
			+ 7;

	private StringBuilder ans_sb;
	private long sum = 0;
	private int[] cnt;

	private void soln()
	{
		int n = nextInt();
		String s = nextLine();
		boolean f = true;
		for (int i = 0; i < n
				- 1; i++)
		{
			if (s.charAt(
					i) == s.charAt(
							i + 1)
					&& s.charAt(
							i) != '?')
			{
				f = false;
				break;
			}
		}
		boolean f1 = false;
		for (int i = 0; i < n; i++)
		{
			if (s.charAt(
					i) == '?')
			{
				if (i != 0
						&& i != n
								- 1
						&& s.charAt(
								i + 1) != s
										.charAt(i
												- 1)
						&& (s.charAt(
								i + 1) != '?')
						&& s.charAt(
								i - 1) != '?')
					continue;
				f1 = true;
			}
		}
		if (f1 & f)
		{
			pw.println(
					"Yes");
		} else
		{
			pw.println(
					"No");
		}
	}

	class BitsetLong
	{

		static final int LOG = 6;
		static final int SIZE = 1 << LOG;
		static final int MASK = SIZE
				- 1;

		private long[] data;

		public BitsetLong(
				int n)
		{
			data = new long[(n >> LOG)
					+ 2];
		}

		void set(
				int i)
		{
			data[i >> LOG] |= 1L << (i
					& MASK);
		}

		void unset(
				int i)
		{
			data[i >> LOG] &= ~(1L << (i
					& MASK));
		}

		void flip(
				int i)
		{
			data[i >> LOG] ^= 1L << (i
					& MASK);
		}

		int get(int i)
		{
			return (int) ((data[i >> LOG] >>> (i
					& MASK))
					& 1);
		}

		void print()
		{
			for (int i = 0; i < data.length; i++)
			{
				System.out
						.print(Long
								.toString(
										data[i],
										2));
			}
			System.out
					.println();
		}

		long getWord(
				int i)
		{
			if (i <= -SIZE
					|| (i >> LOG)
							+ 1 >= data.length)
			{
				return 0;
			}
			int rem = i
					& MASK;
			int idx = i >> LOG;

			if (rem == 0)
			{
				return data[idx];
			}

			long head = idx < 0
					? 0
					: (data[idx] >>> rem);
			long tail = data[idx
					+ 1] << (SIZE
							- rem);

			return head
					| tail;
		}
	}

	int count(
			long[] bs,
			int len)
	{
		int ret = 0;
		for (int i = 0; i << 6 < len; i++)
		{
			if (((i + 1) << 6) <= len)
			{
				ret += Long
						.bitCount(
								bs[i]);
			} else
			{
				int rem = len
						& 63;
				ret += Long
						.bitCount(
								bs[i] << (64
										- rem));
			}
		}
		return ret;
	}

	private class Pair
			implements
			Comparable<Pair>
	{
		int v, i,
				j;

		public Pair(
				int a,
				int b,
				int c)
		{
			v = a;
			i = b;
			j = c;
		}

		@Override
		public int compareTo(
				Pair arg0)
		{
			return this.v
					- arg0.v;
		}
	}

	private class Bridge
	{
		private LinkedList<Edge>[] graph;
		private LinkedList<Integer>[] tree;
		private int t;
		private boolean[] isBridge;
		private int[] cno;

		public Bridge(
				int n,
				int m)
		{
			pre(n, m);
		}

		private class Edge
		{
			int u, v,
					i;

			public Edge(
					int a,
					int b,
					int c)
			{
				u = a;
				v = b;
				i = c;
			}
		}

		private void pre(
				int n,
				int m)
		{
			graph = new LinkedList[n];
			tree = new LinkedList[n];
			for (int i = 0; i < m; i++)
			{
				int u = nextInt()
						- 1;
				int v = nextInt()
						- 1;
				Edge e = new Edge(
						u,
						v,
						i);
				graph[u].add(
						e);
				graph[v].add(
						e);
			}
			isBridge = new boolean[m];
			cno = new int[n];
			boolean[] v = new boolean[n];
			int[] arr = new int[n];
			for (int i = 0; i < n; i++)
				if (!v[i])
					dfs(i, null,
							v,
							arr);
		}

		private int dfs(
				int u,
				Edge e,
				boolean[] v,
				int[] arr)
		{
			v[u] = true;
			arr[u] = t++;
			int min = arr[u];
			Iterator<Edge> it = graph[u]
					.listIterator();
			while (it
					.hasNext())
			{
				Edge x = it
						.next();
				int w = x.u;
				if (x.u == u)
					w = x.v;
				if (!v[w])
					min = Math
							.min(min,
									dfs(w, x,
											v,
											arr));
				else if (x != e)
					min = Math
							.min(min,
									arr[w]);
			}
			if (min == arr[u]
					&& e != null)
				isBridge[e.i] = true;
			return min;
		}

		private void bfs(
				int u,
				int cmpNo,
				Queue<Integer>[] q,
				boolean[] v)
		{
			int cur = cmpNo;
			cno[cur] = cmpNo;
			q[cur].add(
					u);
			v[u] = true;
			while (!q[cur]
					.isEmpty())
			{
				int x = q[cur]
						.poll();
				Iterator<Edge> it = graph[x]
						.listIterator();
				while (it
						.hasNext())
				{
					Edge x1 = it
							.next();
					int w = x1.u;
					if (w == x)
						w = x1.v;
					if (!v[w])
					{
						if (isBridge[x1.i])
						{
							tree[cur]
									.add(0, cmpNo
											+ 1);
							tree[cmpNo
									+ 1].add(
											0,
											cur);
							bfs(w, cmpNo
									+ 1,
									q,
									v);
						} else
						{
							bfs(w, cmpNo,
									q,
									v);
						}
					}
				}
			}
		}
	}

	private String solveEqn(
			long a,
			long b)
	{
		long x = 0,
				y = 1,
				lastx = 1,
				lasty = 0,
				temp;
		while (b != 0)
		{
			long q = a
					/ b;
			long r = a
					% b;
			a = b;
			b = r;
			temp = x;
			x = lastx
					- q * x;
			lastx = temp;
			temp = y;
			y = lasty
					- q * y;
			lasty = temp;
		}
		return lastx
				+ " "
				+ lasty;
	}

	private void debug(
			Object... o)
	{
		System.out
				.println(
						Arrays.deepToString(
								o));
	}

	private long pow(
			long a,
			long b,
			long c)
	{
		if (b == 0)
			return 1;
		long p = pow(
				a,
				b / 2,
				c);
		p = (p * p)
				% c;
		return (b
				% 2 == 0)
						? p
						: (a * p)
								% c;
	}

	private long gcd(
			long n,
			long l)
	{
		if (l == 0)
			return n;
		return gcd(
				l,
				n % l);
	}

	public static void main(
			String[] args)
			throws Exception
	{
		new Thread(
				null,
				new Runnable()
				{
					@Override
					public void run()
					{
						new Main()
								.solve();
					}
				},
				"1",
				1 << 26).start();
		// new Main().solve();
	}

	public StringBuilder solve()
	{
		InputReader(
				System.in);
		/*
		 * try { InputReader(new FileInputStream("C:\\Users\\hardik\\Desktop\\in.txt"));
		 * } catch(FileNotFoundException e) {}
		 */
		pw = new PrintWriter(
				System.out);
		// ans_sb = new StringBuilder();
		soln();

		pw.close();
		// System.out.println(ans_sb);
		return ans_sb;
	}

	public void InputReader(
			InputStream stream1)
	{
		stream = stream1;
	}

	private boolean isWhitespace(
			int c)
	{
		return c == ' '
				|| c == '\n'
				|| c == '\r'
				|| c == '\t'
				|| c == -1;
	}

	private boolean isEndOfLine(
			int c)
	{
		return c == '\n'
				|| c == '\r'
				|| c == -1;
	}

	private int read()
	{
		if (numChars == -1)
			throw new InputMismatchException();
		if (curChar >= numChars)
		{
			curChar = 0;
			try
			{
				numChars = stream
						.read(buf);
			} catch (IOException e)
			{
				throw new InputMismatchException();
			}
			if (numChars <= 0)
				return -1;
		}
		return buf[curChar++];
	}

	private int nextInt()
	{
		int c = read();
		while (isSpaceChar(
				c))
			c = read();
		int sgn = 1;
		if (c == '-')
		{
			sgn = -1;
			c = read();
		}
		int res = 0;
		do
		{
			if (c < '0'
					|| c > '9')
				throw new InputMismatchException();
			res *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(
				c));
		return res
				* sgn;
	}

	private long nextLong()
	{
		int c = read();
		while (isSpaceChar(
				c))
			c = read();
		int sgn = 1;
		if (c == '-')
		{
			sgn = -1;
			c = read();
		}
		long res = 0;
		do
		{
			if (c < '0'
					|| c > '9')
				throw new InputMismatchException();
			res *= 10;
			res += c - '0';
			c = read();
		} while (!isSpaceChar(
				c));
		return res
				* sgn;
	}

	private String nextToken()
	{
		int c = read();
		while (isSpaceChar(
				c))
			c = read();
		StringBuilder res = new StringBuilder();
		do
		{
			res.appendCodePoint(
					c);
			c = read();
		} while (!isSpaceChar(
				c));
		return res
				.toString();
	}

	private String nextLine()
	{
		int c = read();
		while (isSpaceChar(
				c))
			c = read();
		StringBuilder res = new StringBuilder();
		do
		{
			res.appendCodePoint(
					c);
			c = read();
		} while (!isEndOfLine(
				c));
		return res
				.toString();
	}

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

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

	private void pArray(
			int[] arr)
	{
		for (int i = 0; i < arr.length; i++)
		{
			System.out
					.print(arr[i]
							+ " ");
		}
		System.out
				.println();
		return;
	}

	private void pArray(
			long[] arr)
	{
		for (int i = 0; i < arr.length; i++)
		{
			System.out
					.print(arr[i]
							+ " ");
		}
		System.out
				.println();
		return;
	}

	private boolean isSpaceChar(
			int c)
	{
		if (filter != null)
			return filter
					.isSpaceChar(
							c);
		return isWhitespace(
				c);
	}

	private char nextChar()
	{
		int c = read();
		while (isSpaceChar(
				c))
			c = read();
		char c1 = (char) c;
		while (!isSpaceChar(
				c))
			c = read();
		return c1;
	}

	private interface SpaceCharFilter
	{
		public boolean isSpaceChar(
				int ch);
	}
}