Problem: Let's call a string adorable if its letters can be realigned in such a way that they form two consequent groups of equal symbols (note that different groups must contain different symbols). For example, ababa is adorable (you can transform it to aaabb, where the first three letters form a group of a-s and others — a group of b-s), but cccc is not since in each possible consequent partition letters in these two groups coincide.

You're given a string s. Check whether it can be split into two non-empty subsequences such that the strings formed by these subsequences are adorable. Here a subsequence is an arbitrary set of indexes of the string.

Input

The only line contains s (1 ≤ |s| ≤ 105) consisting of lowercase latin letters.

Output

Print «Yes» if the string can be split according to the criteria above or «No» otherwise.

Each letter can be printed in arbitrary case.

Examples

Input

ababa


Output

Yes


Input

zzcxx


Output

Yes


Input

yeee


Output

No

Note

In sample case two zzcxx can be split into subsequences zc and zxx each of which is adorable.

There's no suitable partition in sample case three.

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 q = nextInt(); long limit = 1000000000000000000L; //limit = 591;
		 * ArrayList<Long> set = new ArrayList<>(); for(long j=2;j<=1000000;j++) { long
		 * sqrt = (long) Math.sqrt(j); if(sqrt*sqrt != j) { long pow = j; long pow1 =
		 * j*j; double gg = (((double)limit)/((double)pow1)); if(gg >= pow) for(long
		 * i=3;i<=63;i+=2) { pow *= pow1; if(pow<= 0) break; set.add(pow); if(gg < pow)
		 * break; } } } //debug(set); Collections.sort(set); TreeMap<Long, Integer> map
		 * = new TreeMap<>(); int k = 1; long prev = -1; for(long x:set) {
		 * //if(!map.containsKey(x)) if(x != prev) map.put(x, k++); prev = x; }
		 * while(q-- > 0) { long l = nextLong(); long r = nextLong(); Long k1 =
		 * map.floorKey(r); //debug((long)Math.floor(Math.sqrt(r))); long ans =
		 * (long)Math.floor(Math.sqrt(r)); long l1 = 1; long r1 = ans; long a1 = 0;
		 * while(l1 <= r1) { long mid = (l1 + r1)/2; if(mid*mid <= l-1) { l1 = mid + 1;
		 * a1 = mid; }else r1 = mid - 1; } ans -= a1; //debug(ans); if(k1 != null) { ans
		 * += (long)map.get(k1); } Long k2 = map.floorKey(l - 1); if(k2 != null) { ans
		 * -= (long)map.get(k2); } pw.println(ans); }
		 */

		HashMap<Character, Integer> hm = new HashMap<>();
		String s = nextLine();
		char ch[] = s
				.toCharArray();
		for (char c : ch)
		{
			if (hm.containsKey(
					c))
			{
				hm.put(c,
						hm.get(c)
								+ 1);
			} else
				hm.put(c,
						1);
		}
		int n = hm
				.size();
		// System.out.println(hm);
		if (n > 4)
		{
			System.out
					.println(
							"No");
		} else if (n == 1)
		{
			System.out
					.println(
							"No");
		} else if (n == 2)
		{
			boolean b = false;
			for (char i : hm
					.keySet())
			{
				if (hm.get(
						i) <= 1)
					b = true;
			}
			if (b)
				System.out
						.println(
								"No");
			else
				System.out
						.println(
								"Yes");
		} else if (n == 3)
		{
			boolean b = false;
			for (char i : hm
					.keySet())
			{
				if (hm.get(
						i) > 1)
					b = true;
			}
			if (b)
				System.out
						.println(
								"Yes");
			else
				System.out
						.println(
								"No");
		} else if (n == 4)
		{
			System.out
					.println(
							"Yes");
		}
	}

	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);
	}
}