Problem: Mashmokh's boss, Bimokh, didn't like Mashmokh. So he fired him. Mashmokh decided to go to university and participate in ACM instead of finding a new job. He wants to become a member of Bamokh's team. In order to join he was given some programming tasks and one week to solve them. Mashmokh is not a very experienced programmer. Actually he is not a programmer at all. So he wasn't able to solve them. That's why he asked you to help him with these tasks. One of these tasks is the following.

A sequence of l integers b1, b2, ..., bl (1 ≤ b1 ≤ b2 ≤ ... ≤ bl ≤ n) is called good if each number divides (without a remainder) by the next number in the sequence. More formally <image> for all i (1 ≤ i ≤ l - 1).

Given n and k find the number of good sequences of length k. As the answer can be rather large print it modulo 1000000007 (109 + 7).

Input

The first line of input contains two space-separated integers n, k (1 ≤ n, k ≤ 2000).

Output

Output a single integer — the number of good sequences of length k modulo 1000000007 (109 + 7).

Examples

Input

3 2


Output

5


Input

6 4


Output

39


Input

2 1


Output

2

Note

In the first sample the good sequences are: [1, 1], [2, 2], [3, 3], [1, 2], [1, 3].

Solution (in JAVA):

Solution:
import java.util.*;
import java.io.*;
import java.math.*;
import java.lang.reflect.*;

public class Main {
	public static void main(String[] args) {
		InputStream inputStream = System.in;
		OutputStream outputStream = System.out;
		InputReader in = new InputReader(inputStream);
		OutputWriter out = new OutputWriter(outputStream);
		Task solver = new TaskD();
		solver.solve(1, in, out);
		out.close();
	}
}

interface Task {
	public void solve(int testNumber, InputReader in, OutputWriter out);
}

class TaskA implements Task {

	public void solve(int testNumber, InputReader in, OutputWriter out) {
		long a=in.readLong(), b=in.readLong();
		out.printLine(f(a, b));
	}
	
	long f(long a, long b) {
		if (b==1) return a;
		if (a==1) return b;
		if (a>b) return a/b+f(a%b, b);
		return b/a+f(b%a, a);
	}

}

class TaskB implements Task {
	
	public void solve(int testNumber, InputReader in, OutputWriter out) {
		int a=in.readInt(), b=in.readInt(), c=in.readInt(), ret=0, mod=1<<30;
		for (int i=1; i<=a; i++) for (int j=1; j<=b; j++) for (int k=1; k<=c; k++) {
			int x=i*j*k,y=1, z;
			for (int l=2; l*l<=x; l++) {
				z=1;
				while (x%l==0) {
					z++;
					x/=l;
				}
				y*=z;
			}
			if (x>1) y*=2;
			ret+=y;
		}
		out.printLine(ret);
	}

}

class TaskC implements Task {

	public void solve(int testNumber, InputReader in, OutputWriter out) {
		int n=in.readInt();
		long ret=Long.MIN_VALUE;
		for (int i=MiscUtils.max(1, n-100); i<=n; i++) for (int j=i; j<=n; j++) for (int k=j; k<=n; k++) 
			ret=MiscUtils.max(ret, IntegerUtils.lcm(IntegerUtils.lcm(i, j), k));
		out.printLine(ret);
	}

}

class TaskD implements Task {

	long[][] dp;
	List<List<Long>> list;
	
	public void solve(int testNumber, InputReader in, OutputWriter out) {
		int n=in.readInt(), k=in.readInt(), mod=1000000007;
		dp=new long[k+1][n+1];
		Arrays.fill(dp[1], 1L);
		list=new ArrayList<List<Long>>();
		for (int i=0; i<=n; i++) list.add(IntegerUtils.getDivisors(i));
		for (int i=2; i<=k; i++) for (int j=1; j<=n; j++) for (long x: list.get(j)) dp[i][j]=(dp[i][j]+dp[i-1][(int)x])%mod;
		long ret=0L;
		for (int i=1; i<=n; i++) ret=(ret+dp[k][i])%mod;
		out.printLine(ret);
	}
}

class TaskE implements Task {

	public void solve(int testNumber, InputReader in, OutputWriter out) {

	}

}

class TaskF implements Task {

	public void solve(int testNumber, InputReader in, OutputWriter out) {

	}

}

class OutputWriter {
	private final PrintWriter writer;

	public OutputWriter(OutputStream outputStream) {
		writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
				outputStream)));
	}

	public OutputWriter(Writer writer) {
		this.writer = new PrintWriter(writer);
	}

	public void print(char[] array) {
		writer.print(array);
	}

	public void print(Object... objects) {
		for (int i = 0; i < objects.length; i++) {
			if (i != 0)
				writer.print(' ');
			writer.print(objects[i]);
		}
	}

	public void print(int[] array) {
		for (int i = 0; i < array.length; i++) {
			if (i != 0)
				writer.print(' ');
			writer.print(array[i]);
		}
	}

	public void print(long[] array) {
		for (int i = 0; i < array.length; i++) {
			if (i != 0)
				writer.print(' ');
			writer.print(array[i]);
		}
	}

	public void print(Collection<Integer> collection) {
		boolean first = true;
		for (int value : collection) {
			if (first)
				first = false;
			else
				writer.print(' ');
			writer.print(value);
		}
	}

	public void printLine(int[] array) {
		print(array);
		writer.println();
	}

	public void printLine(long[] array) {
		print(array);
		writer.println();
	}

	public void printLine(Collection<Integer> collection) {
		print(collection);
		writer.println();
	}

	public void printLine() {
		writer.println();
	}

	public void printLine(Object... objects) {
		print(objects);
		writer.println();
	}

	public void print(char i) {
		writer.print(i);
	}

	public void printLine(char i) {
		writer.println(i);
	}

	public void printLine(char[] array) {
		writer.println(array);
	}

	public void printFormat(String format, Object... objects) {
		writer.printf(format, objects);
	}

	public void close() {
		writer.close();
	}

	public void flush() {
		writer.flush();
	}

	public void print(long i) {
		writer.print(i);
	}

	public void printLine(long i) {
		writer.println(i);
	}

	public void print(int i) {
		writer.print(i);
	}

	public void printLine(int i) {
		writer.println(i);
	}
}

class InputReader {
	private boolean finished = false;

	private InputStream stream;
	private byte[] buf = new byte[1024];
	private int curChar;
	private int numChars;
	private SpaceCharFilter filter;

	public InputReader(InputStream stream) {
		this.stream = stream;
	}

	public 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++];
	}

	public int peek() {
		if (numChars == -1)
			return -1;
		if (curChar >= numChars) {
			curChar = 0;
			try {
				numChars = stream.read(buf);
			} catch (IOException e) {
				return -1;
			}
			if (numChars <= 0)
				return -1;
		}
		return buf[curChar];
	}

	public int readInt() {
		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;
	}

	public long readLong() {
		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;
	}

	public String readString() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		StringBuilder res = new StringBuilder();
		do {
			if (Character.isValidCodePoint(c))
				res.appendCodePoint(c);
			c = read();
		} while (!isSpaceChar(c));
		return res.toString();
	}

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

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

	private String readLine0() {
		StringBuilder buf = new StringBuilder();
		int c = read();
		while (c != '\n' && c != -1) {
			if (c != '\r')
				buf.appendCodePoint(c);
			c = read();
		}
		return buf.toString();
	}

	public String readLine() {
		String s = readLine0();
		while (s.trim().length() == 0)
			s = readLine0();
		return s;
	}

	public String readLine(boolean ignoreEmptyLines) {
		if (ignoreEmptyLines)
			return readLine();
		else
			return readLine0();
	}

	public BigInteger readBigInteger() {
		try {
			return new BigInteger(readString());
		} catch (NumberFormatException e) {
			throw new InputMismatchException();
		}
	}

	public char readCharacter() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		return (char) c;
	}

	public double readDouble() {
		int c = read();
		while (isSpaceChar(c))
			c = read();
		int sgn = 1;
		if (c == '-') {
			sgn = -1;
			c = read();
		}
		double res = 0;
		while (!isSpaceChar(c) && c != '.') {
			if (c == 'e' || c == 'E')
				return res * Math.pow(10, readInt());
			if (c < '0' || c > '9')
				throw new InputMismatchException();
			res *= 10;
			res += c - '0';
			c = read();
		}
		if (c == '.') {
			c = read();
			double m = 1;
			while (!isSpaceChar(c)) {
				if (c == 'e' || c == 'E')
					return res * Math.pow(10, readInt());
				if (c < '0' || c > '9')
					throw new InputMismatchException();
				m /= 10;
				res += (c - '0') * m;
				c = read();
			}
		}
		return res * sgn;
	}

	public boolean isExhausted() {
		int value;
		while (isSpaceChar(value = peek()) && value != -1)
			read();
		return value == -1;
	}

	public String next() {
		return readString();
	}

	public SpaceCharFilter getFilter() {
		return filter;
	}

	public void setFilter(SpaceCharFilter filter) {
		this.filter = filter;
	}

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

class IOUtils {
	public static Pair<Integer, Integer> readIntPair(InputReader in) {
		int first = in.readInt();
		int second = in.readInt();
		return Pair.makePair(first, second);
	}

	public static Pair<Long, Long> readLongPair(InputReader in) {
		long first = in.readLong();
		long second = in.readLong();
		return Pair.makePair(first, second);
	}

	public static int[] readIntArray(InputReader in, int size) {
		int[] array = new int[size];
		for (int i = 0; i < size; i++)
			array[i] = in.readInt();
		return array;
	}

	public static long[] readLongArray(InputReader in, int size) {
		long[] array = new long[size];
		for (int i = 0; i < size; i++)
			array[i] = in.readLong();
		return array;
	}

	public static double[] readDoubleArray(InputReader in, int size) {
		double[] array = new double[size];
		for (int i = 0; i < size; i++)
			array[i] = in.readDouble();
		return array;
	}

	public static String[] readStringArray(InputReader in, int size) {
		String[] array = new String[size];
		for (int i = 0; i < size; i++)
			array[i] = in.readString();
		return array;
	}

	public static char[] readCharArray(InputReader in, int size) {
		char[] array = new char[size];
		for (int i = 0; i < size; i++)
			array[i] = in.readCharacter();
		return array;
	}

	public static Pair<Integer, Integer>[] readIntPairArray(InputReader in,
			int size) {
		@SuppressWarnings({ "unchecked" })
		Pair<Integer, Integer>[] result = new Pair[size];
		for (int i = 0; i < size; i++)
			result[i] = readIntPair(in);
		return result;
	}

	public static Pair<Long, Long>[] readLongPairArray(InputReader in, int size) {
		@SuppressWarnings({ "unchecked" })
		Pair<Long, Long>[] result = new Pair[size];
		for (int i = 0; i < size; i++)
			result[i] = readLongPair(in);
		return result;
	}

	public static void readIntArrays(InputReader in, int[]... arrays) {
		for (int i = 0; i < arrays[0].length; i++) {
			for (int j = 0; j < arrays.length; j++)
				arrays[j][i] = in.readInt();
		}
	}

	public static void readLongArrays(InputReader in, long[]... arrays) {
		for (int i = 0; i < arrays[0].length; i++) {
			for (int j = 0; j < arrays.length; j++)
				arrays[j][i] = in.readLong();
		}
	}

	public static void readDoubleArrays(InputReader in, double[]... arrays) {
		for (int i = 0; i < arrays[0].length; i++) {
			for (int j = 0; j < arrays.length; j++)
				arrays[j][i] = in.readDouble();
		}
	}

	public static char[][] readTable(InputReader in, int rowCount,
			int columnCount) {
		char[][] table = new char[rowCount][];
		for (int i = 0; i < rowCount; i++)
			table[i] = readCharArray(in, columnCount);
		return table;
	}

	public static int[][] readIntTable(InputReader in, int rowCount,
			int columnCount) {
		int[][] table = new int[rowCount][];
		for (int i = 0; i < rowCount; i++)
			table[i] = readIntArray(in, columnCount);
		return table;
	}

	public static double[][] readDoubleTable(InputReader in, int rowCount,
			int columnCount) {
		double[][] table = new double[rowCount][];
		for (int i = 0; i < rowCount; i++)
			table[i] = readDoubleArray(in, columnCount);
		return table;
	}

	public static long[][] readLongTable(InputReader in, int rowCount,
			int columnCount) {
		long[][] table = new long[rowCount][];
		for (int i = 0; i < rowCount; i++)
			table[i] = readLongArray(in, columnCount);
		return table;
	}

	public static String[][] readStringTable(InputReader in, int rowCount,
			int columnCount) {
		String[][] table = new String[rowCount][];
		for (int i = 0; i < rowCount; i++)
			table[i] = readStringArray(in, columnCount);
		return table;
	}

	public static String readText(InputReader in) {
		StringBuilder result = new StringBuilder();
		while (true) {
			int character = in.read();
			if (character == '\r')
				continue;
			if (character == -1)
				break;
			result.append((char) character);
		}
		return result.toString();
	}

	public static void readStringArrays(InputReader in, String[]... arrays) {
		for (int i = 0; i < arrays[0].length; i++) {
			for (int j = 0; j < arrays.length; j++)
				arrays[j][i] = in.readString();
		}
	}

	public static void printTable(OutputWriter out, char[][] table) {
		for (char[] row : table)
			out.printLine(new String(row));
	}
}

class ArrayUtils {
	private static int[] tempInt = new int[0];
	private static long[] tempLong = new long[0];

	public static Integer[] generateOrder(int size) {
		Integer[] order = new Integer[size];
		for (int i = 0; i < size; i++)
			order[i] = i;
		return order;
	}

	public static void fill(short[][] array, short value) {
		for (short[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(long[][] array, long value) {
		for (long[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(double[][] array, double value) {
		for (double[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(double[][][] array, double value) {
		for (double[][] row : array)
			fill(row, value);
	}

	public static void fill(double[][][][] array, double value) {
		for (double[][][] row : array)
			fill(row, value);
	}

	public static void fill(double[][][][][] array, double value) {
		for (double[][][][] row : array)
			fill(row, value);
	}

	public static void fill(long[][][] array, long value) {
		for (long[][] row : array)
			fill(row, value);
	}

	public static void fill(long[][][][] array, long value) {
		for (long[][][] row : array)
			fill(row, value);
	}

	public static void fill(long[][][][][] array, long value) {
		for (long[][][][] row : array)
			fill(row, value);
	}

	public static void fillColumn(long[][] array, int index, long value) {
		for (long[] row : array)
			row[index] = value;
	}

	public static void fillColumn(int[][] array, int index, int value) {
		for (int[] row : array)
			row[index] = value;
	}

	public static void fill(int[][] array, int value) {
		for (int[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(boolean[][] array, boolean value) {
		for (boolean[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(boolean[][][] array, boolean value) {
		for (boolean[][] row : array)
			fill(row, value);
	}

	public static long sumArray(int[] array) {
		long result = 0;
		for (int element : array)
			result += element;
		return result;
	}

	public static int[] range(int from, int to) {
		int[] result = new int[Math.max(from, to) - Math.min(from, to) + 1];
		int index = 0;
		if (to > from) {
			for (int i = from; i <= to; i++)
				result[index++] = i;
		} else {
			for (int i = from; i >= to; i--)
				result[index++] = i;
		}
		return result;
	}

	public static void fill(int[][][] array, int value) {
		for (int[][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(short[][][] array, short value) {
		for (short[][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(int[][][][] array, int value) {
		for (int[][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(short[][][][] array, short value) {
		for (short[][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(int[][][][][] array, int value) {
		for (int[][][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(short[][][][][] array, short value) {
		for (short[][][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(int[][][][][][] array, int value) {
		for (int[][][][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(short[][][][][][] array, short value) {
		for (short[][][][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(int[][][][][][][] array, int value) {
		for (int[][][][][][] subArray : array)
			fill(subArray, value);
	}

	public static void fill(short[][][][][][][] array, short value) {
		for (short[][][][][][] subArray : array)
			fill(subArray, value);
	}

	public static Integer[] order(int size, Comparator<Integer> comparator) {
		Integer[] order = generateOrder(size);
		Arrays.sort(order, comparator);
		return order;
	}

	public static <T> void fill(T[][] array, T value) {
		for (T[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(char[][] array, char value) {
		for (char[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(byte[][] array, byte value) {
		for (byte[] row : array)
			Arrays.fill(row, value);
	}

	public static void fill(byte[][][] array, byte value) {
		for (byte[][] row : array)
			fill(row, value);
	}

	public static void fill(byte[][][][] array, byte value) {
		for (byte[][][] row : array)
			fill(row, value);
	}

	public static long multiply(int[] first, int[] second) {
		long result = 0;
		for (int i = 0; i < first.length; i++)
			result += (long) first[i] * second[i];
		return result;
	}

	public static int[] createOrder(int size) {
		int[] order = new int[size];
		for (int i = 0; i < size; i++)
			order[i] = i;
		return order;
	}

	public static int[] sort(int[] array, IntComparator comparator) {
		return sort(array, 0, array.length, comparator);
	}

	public static int[] sort(int[] array, int from, int to,
			IntComparator comparator) {
		Integer[] intArray = new Integer[to - from];
		for (int i = from; i < to; i++)
			intArray[i - from] = array[i];
		Arrays.sort(intArray, comparator);
		for (int i=from; i<to; i++) array[i]=intArray[i-from];
		return array;
	}

	private static void ensureCapacityInt(int size) {
		if (tempInt.length >= size)
			return;
		size = Math.max(size, tempInt.length << 1);
		tempInt = new int[size];
	}

	private static void ensureCapacityLong(int size) {
		if (tempLong.length >= size)
			return;
		size = Math.max(size, tempLong.length << 1);
		tempLong = new long[size];
	}

	private static void sortImpl(int[] array, int from, int to, int[] temp,
			int fromTemp, int toTemp, IntComparator comparator) {
		if (to - from <= 1)
			return;
		int middle = (to - from) >> 1;
		int tempMiddle = fromTemp + middle;
		sortImpl(temp, fromTemp, tempMiddle, array, from, from + middle,
				comparator);
		sortImpl(temp, tempMiddle, toTemp, array, from + middle, to, comparator);
		int index = from;
		int index1 = fromTemp;
		int index2 = tempMiddle;
		while (index1 < tempMiddle && index2 < toTemp) {
			if (comparator.compare(temp[index1], temp[index2]) <= 0)
				array[index++] = temp[index1++];
			else
				array[index++] = temp[index2++];
		}
		if (index1 != tempMiddle)
			System.arraycopy(temp, index1, array, index, tempMiddle - index1);
		if (index2 != toTemp)
			System.arraycopy(temp, index2, array, index, toTemp - index2);
	}

	public static int[] order(final int[] array) {
		return sort(createOrder(array.length), new IntComparator() {
			public int compare(Integer first, Integer second) {
				if (array[first] < array[second])
					return -1;
				if (array[first] > array[second])
					return 1;
				return 0;
			}
		});
	}

	public static int[] order(final long[] array) {
		return sort(createOrder(array.length), new IntComparator() {
			public int compare(Integer first, Integer second) {
				if (array[first] < array[second])
					return -1;
				if (array[first] > array[second])
					return 1;
				return 0;
			}
		});
	}

	public static int[] unique(int[] array) {
		return unique(array, 0, array.length);
	}

	public static int[] unique(int[] array, int from, int to) {
		if (from == to)
			return new int[0];
		int count = 1;
		for (int i = from + 1; i < to; i++) {
			if (array[i] != array[i - 1])
				count++;
		}
		int[] result = new int[count];
		result[0] = array[from];
		int index = 1;
		for (int i = from + 1; i < to; i++) {
			if (array[i] != array[i - 1])
				result[index++] = array[i];
		}
		return result;
	}

	public static char[] unique(char[] array) {
		return unique(array, 0, array.length);
	}

	public static char[] unique(char[] array, int from, int to) {
		if (from == to)
			return new char[0];
		int count = 1;
		for (int i = from + 1; i < to; i++) {
			if (array[i] != array[i - 1])
				count++;
		}
		char[] result = new char[count];
		result[0] = array[from];
		int index = 1;
		for (int i = from + 1; i < to; i++) {
			if (array[i] != array[i - 1])
				result[index++] = array[i];
		}
		return result;
	}

	public static int maxElement(int[] array) {
		return maxElement(array, 0, array.length);
	}

	public static int maxElement(int[] array, int from, int to) {
		int result = Integer.MIN_VALUE;
		for (int i = from; i < to; i++)
			result = Math.max(result, array[i]);
		return result;
	}

	public static int[] order(final double[] array) {
		return sort(createOrder(array.length), new IntComparator() {
			public int compare(Integer first, Integer second) {
				return Double.compare(array[first], array[second]);
			}
		});
	}

	public static int[] reversePermutation(int[] permutation) {
		int[] result = new int[permutation.length];
		for (int i = 0; i < permutation.length; i++)
			result[permutation[i]] = i;
		return result;
	}

	public static void reverse(int[] array) {
		for (int i = 0, j = array.length - 1; i < j; i++, j--) {
			int temp = array[i];
			array[i] = array[j];
			array[j] = temp;
		}
	}

	public static void reverse(char[] array) {
		for (int i = 0, j = array.length - 1; i < j; i++, j--) {
			char temp = array[i];
			array[i] = array[j];
			array[j] = temp;
		}
	}

	private static long maxElement(long[] array, int from, int to) {
		long result = Long.MIN_VALUE;
		for (int i = from; i < to; i++)
			result = Math.max(result, array[i]);
		return result;
	}

	public static int minPosition(int[] array) {
		return minPosition(array, 0, array.length);
	}

	public static int maxPosition(int[] array) {
		return maxPosition(array, 0, array.length);
	}

	public static int minPosition(int[] array, int from, int to) {
		if (from >= to)
			return -1;
		int min = array[from];
		int result = from;
		for (int i = from + 1; i < to; i++) {
			if (array[i] < min) {
				min = array[i];
				result = i;
			}
		}
		return result;
	}

	public static int maxPosition(int[] array, int from, int to) {
		if (from >= to)
			return -1;
		int max = array[from];
		int result = from;
		for (int i = from + 1; i < to; i++) {
			if (array[i] > max) {
				max = array[i];
				result = i;
			}
		}
		return result;
	}

	public static int[] multiplyPermutations(int[] first, int[] second) {
		int count = first.length;
		int[] result = new int[count];
		for (int i = 0; i < count; i++) {
			result[i] = first[second[i]];
		}
		return result;
	}

	public static int[] compress(int[]... arrays) {
		int totalLength = 0;
		for (int[] array : arrays)
			totalLength += array.length;
		int[] all = new int[totalLength];
		int delta = 0;
		for (int[] array : arrays) {
			System.arraycopy(array, 0, all, delta, array.length);
			delta += array.length;
		}
		sort(all, IntComparator.DEFAULT);
		all = unique(all);
		for (int[] array : arrays) {
			for (int i = 0; i < array.length; i++)
				array[i] = Arrays.binarySearch(all, array[i]);
		}
		return all;
	}

	public static int minElement(int[] array) {
		return array[minPosition(array)];
	}

	public static long[] partialSums(int[] array) {
		long[] result = new long[array.length + 1];
		for (int i = 0; i < array.length; i++)
			result[i + 1] = result[i] + array[i];
		return result;
	}

	public static void orderBy(int[] base, int[]... arrays) {
		int[] order = ArrayUtils.order(base);
		order(order, base);
		for (int[] array : arrays)
			order(order, array);
	}

	public static void orderBy(long[] base, long[]... arrays) {
		int[] order = ArrayUtils.order(base);
		order(order, base);
		for (long[] array : arrays)
			order(order, array);
	}

	public static void order(int[] order, int[] array) {
		ensureCapacityInt(order.length);
		for (int i = 0; i < order.length; i++)
			tempInt[i] = array[order[i]];
		System.arraycopy(tempInt, 0, array, 0, array.length);
	}

	public static void order(int[] order, long[] array) {
		ensureCapacityLong(order.length);
		for (int i = 0; i < order.length; i++)
			tempLong[i] = array[order[i]];
		System.arraycopy(tempLong, 0, array, 0, array.length);
	}

	public static long[] asLong(int[] array) {
		long[] result = new long[array.length];
		for (int i = 0; i < array.length; i++)
			result[i] = array[i];
		return result;
	}

	public static int count(int[] array, int value) {
		int result = 0;
		for (int i : array) {
			if (i == value)
				result++;
		}
		return result;
	}

	public static int count(char[] array, char value) {
		int result = 0;
		for (char i : array) {
			if (i == value)
				result++;
		}
		return result;
	}

	public static int count(boolean[] array, boolean value) {
		int result = 0;
		for (boolean i : array) {
			if (i == value)
				result++;
		}
		return result;
	}

	public static int[] merge(int[] first, int[] second) {
		int[] result = new int[first.length + second.length];
		int firstIndex = 0;
		int secondIndex = 0;
		int index = 0;
		while (firstIndex < first.length && secondIndex < second.length) {
			if (first[firstIndex] < second[secondIndex])
				result[index++] = first[firstIndex++];
			else
				result[index++] = second[secondIndex++];
		}
		System.arraycopy(first, firstIndex, result, index, first.length
				- firstIndex);
		System.arraycopy(second, secondIndex, result, index, second.length
				- secondIndex);
		return result;
	}

	public static boolean nextPermutation(int[] array) {
		return nextPermutation(array, IntComparator.DEFAULT);
	}

	private static boolean nextPermutation(int[] array, IntComparator comparator) {
		int size = array.length;
		int last = array[size - 1];
		for (int i = size - 2; i >= 0; i--) {
			int current = array[i];
			if (comparator.compare(last, current) > 0) {
				for (int j = size - 1; j > i; j--) {
					if (comparator.compare(array[j], current) > 0) {
						swap(array, i, j);
						inPlaceReverse(array, i + 1, size);
						return true;
					}
				}
			}
			last = current;
		}
		return false;
	}

	private static void inPlaceReverse(int[] array, int first, int second) {
		for (int i = first, j = second - 1; i < j; i++, j--)
			swap(array, i, j);
	}

	private static void swap(int[] array, int first, int second) {
		if (first == second)
			return;
		int temp = array[first];
		array[first] = array[second];
		array[second] = temp;
	}

	public static <V> void reverse(V[] array) {
		for (int i = 0, j = array.length - 1; i < j; i++, j--) {
			V temp = array[i];
			array[i] = array[j];
			array[j] = temp;
		}
	}

	public static IntComparator compareBy(final int[]... arrays) {
		return new IntComparator() {
			public int compare(Integer first, Integer second) {
				for (int[] array : arrays) {
					if (array[first] != array[second])
						return Integer.compare(array[first], array[second]);
				}
				return 0;
			}
		};
	}

	public static long minElement(long[] array) {
		return array[minPosition(array)];
	}

	public static long maxElement(long[] array) {
		return array[maxPosition(array)];
	}

	public static int minPosition(long[] array) {
		return minPosition(array, 0, array.length);
	}

	public static int maxPosition(long[] array) {
		return maxPosition(array, 0, array.length);
	}

	public static int minPosition(long[] array, int from, int to) {
		if (from >= to)
			return -1;
		long min = array[from];
		int result = from;
		for (int i = from + 1; i < to; i++) {
			if (array[i] < min) {
				min = array[i];
				result = i;
			}
		}
		return result;
	}

	public static int maxPosition(long[] array, int from, int to) {
		if (from >= to)
			return -1;
		long max = array[from];
		int result = from;
		for (int i = from + 1; i < to; i++) {
			if (array[i] > max) {
				max = array[i];
				result = i;
			}
		}
		return result;
	}

	public static int[] createArray(int count, int value) {
		int[] array = new int[count];
		Arrays.fill(array, value);
		return array;
	}

	public static long[] createArray(int count, long value) {
		long[] array = new long[count];
		Arrays.fill(array, value);
		return array;
	}

	public static double[] createArray(int count, double value) {
		double[] array = new double[count];
		Arrays.fill(array, value);
		return array;
	}

	public static boolean[] createArray(int count, boolean value) {
		boolean[] array = new boolean[count];
		Arrays.fill(array, value);
		return array;
	}

	public static char[] createArray(int count, char value) {
		char[] array = new char[count];
		Arrays.fill(array, value);
		return array;
	}

	public static <T> T[] createArray(int count, T value) {
		@SuppressWarnings("unchecked")
		T[] array = (T[]) Array.newInstance(value.getClass(), count);
		Arrays.fill(array, value);
		return array;
	}
}

class Graph {
	public static final int REMOVED_BIT = 0;

	protected int vertexCount;
	protected int edgeCount;

	private int[] firstOutbound;
	private int[] firstInbound;

	private Edge[] edges;
	private int[] nextInbound;
	private int[] nextOutbound;
	private int[] from;
	private int[] to;
	private long[] weight;
	private long[] capacity;
	private int[] reverseEdge;
	private int[] flags;

	public Graph(int vertexCount) {
		this(vertexCount, vertexCount);
	}

	public Graph(int vertexCount, int edgeCapacity) {
		this.vertexCount = vertexCount;
		firstOutbound = new int[vertexCount];
		Arrays.fill(firstOutbound, -1);

		from = new int[edgeCapacity];
		to = new int[edgeCapacity];
		nextOutbound = new int[edgeCapacity];
		flags = new int[edgeCapacity];
	}

	public static Graph createGraph(int vertexCount, int[] from, int[] to) {
		Graph graph = new Graph(vertexCount, from.length);
		for (int i = 0; i < from.length; i++)
			graph.addSimpleEdge(from[i], to[i]);
		return graph;
	}

	public static Graph createWeightedGraph(int vertexCount, int[] from,
			int[] to, long[] weight) {
		Graph graph = new Graph(vertexCount, from.length);
		for (int i = 0; i < from.length; i++)
			graph.addWeightedEdge(from[i], to[i], weight[i]);
		return graph;
	}

	public static Graph createFlowGraph(int vertexCount, int[] from, int[] to,
			long[] capacity) {
		Graph graph = new Graph(vertexCount, from.length * 2);
		for (int i = 0; i < from.length; i++)
			graph.addFlowEdge(from[i], to[i], capacity[i]);
		return graph;
	}

	public static Graph createFlowWeightedGraph(int vertexCount, int[] from,
			int[] to, long[] weight, long[] capacity) {
		Graph graph = new Graph(vertexCount, from.length * 2);
		for (int i = 0; i < from.length; i++)
			graph.addFlowWeightedEdge(from[i], to[i], weight[i], capacity[i]);
		return graph;
	}

	public static Graph createTree(int[] parent) {
		Graph graph = new Graph(parent.length + 1, parent.length);
		for (int i = 0; i < parent.length; i++)
			graph.addSimpleEdge(parent[i], i + 1);
		return graph;
	}

	public int addEdge(int fromID, int toID, long weight, long capacity,
			int reverseEdge) {
		ensureEdgeCapacity(edgeCount + 1);
		if (firstOutbound[fromID] != -1)
			nextOutbound[edgeCount] = firstOutbound[fromID];
		else
			nextOutbound[edgeCount] = -1;
		firstOutbound[fromID] = edgeCount;
		if (firstInbound != null) {
			if (firstInbound[toID] != -1)
				nextInbound[edgeCount] = firstInbound[toID];
			else
				nextInbound[edgeCount] = -1;
			firstInbound[toID] = edgeCount;
		}
		this.from[edgeCount] = fromID;
		this.to[edgeCount] = toID;
		if (capacity != 0) {
			if (this.capacity == null)
				this.capacity = new long[from.length];
			this.capacity[edgeCount] = capacity;
		}
		if (weight != 0) {
			if (this.weight == null)
				this.weight = new long[from.length];
			this.weight[edgeCount] = weight;
		}
		if (reverseEdge != -1) {
			if (this.reverseEdge == null) {
				this.reverseEdge = new int[from.length];
				Arrays.fill(this.reverseEdge, 0, edgeCount, -1);
			}
			this.reverseEdge[edgeCount] = reverseEdge;
		}
		if (edges != null)
			edges[edgeCount] = createEdge(edgeCount);
		return edgeCount++;
	}

	protected final GraphEdge createEdge(int id) {
		return new GraphEdge(id);
	}

	public final int addFlowWeightedEdge(int from, int to, long weight,
			long capacity) {
		if (capacity == 0) {
			return addEdge(from, to, weight, 0, -1);
		} else {
			int lastEdgeCount = edgeCount;
			addEdge(to, from, -weight, 0, lastEdgeCount + entriesPerEdge());
			return addEdge(from, to, weight, capacity, lastEdgeCount);
		}
	}

	protected int entriesPerEdge() {
		return 1;
	}

	public final int addFlowEdge(int from, int to, long capacity) {
		return addFlowWeightedEdge(from, to, 0, capacity);
	}

	public final int addWeightedEdge(int from, int to, long weight) {
		return addFlowWeightedEdge(from, to, weight, 0);
	}

	public final int addSimpleEdge(int from, int to) {
		return addWeightedEdge(from, to, 0);
	}

	public final int vertexCount() {
		return vertexCount;
	}

	public final int edgeCount() {
		return edgeCount;
	}

	protected final int edgeCapacity() {
		return from.length;
	}

	public final Edge edge(int id) {
		initEdges();
		return edges[id];
	}

	public final int firstOutbound(int vertex) {
		int id = firstOutbound[vertex];
		while (id != -1 && isRemoved(id))
			id = nextOutbound[id];
		return id;
	}

	public final int nextOutbound(int id) {
		id = nextOutbound[id];
		while (id != -1 && isRemoved(id))
			id = nextOutbound[id];
		return id;
	}

	public final int firstInbound(int vertex) {
		initInbound();
		int id = firstInbound[vertex];
		while (id != -1 && isRemoved(id))
			id = nextInbound[id];
		return id;
	}

	public final int nextInbound(int id) {
		initInbound();
		id = nextInbound[id];
		while (id != -1 && isRemoved(id))
			id = nextInbound[id];
		return id;
	}

	public final int source(int id) {
		return from[id];
	}

	public final int destination(int id) {
		return to[id];
	}

	public final long weight(int id) {
		if (weight == null)
			return 0;
		return weight[id];
	}

	public final long capacity(int id) {
		if (capacity == null)
			return 0;
		return capacity[id];
	}

	public final long flow(int id) {
		if (reverseEdge == null)
			return 0;
		return capacity[reverseEdge[id]];
	}

	public final void pushFlow(int id, long flow) {
		if (flow == 0)
			return;
		if (flow > 0) {
			if (capacity(id) < flow)
				throw new IllegalArgumentException("Not enough capacity");
		} else {
			if (flow(id) < -flow)
				throw new IllegalArgumentException("Not enough capacity");
		}
		capacity[id] -= flow;
		capacity[reverseEdge[id]] += flow;
	}

	public int transposed(int id) {
		return -1;
	}

	public final int reverse(int id) {
		if (reverseEdge == null)
			return -1;
		return reverseEdge[id];
	}

	public final void addVertices(int count) {
		ensureVertexCapacity(vertexCount + count);
		Arrays.fill(firstOutbound, vertexCount, vertexCount + count, -1);
		if (firstInbound != null)
			Arrays.fill(firstInbound, vertexCount, vertexCount + count, -1);
		vertexCount += count;
	}

	protected final void initEdges() {
		if (edges == null) {
			edges = new Edge[from.length];
			for (int i = 0; i < edgeCount; i++)
				edges[i] = createEdge(i);
		}
	}

	public final void removeVertex(int vertex) {
		int id = firstOutbound[vertex];
		while (id != -1) {
			removeEdge(id);
			id = nextOutbound[id];
		}
		initInbound();
		id = firstInbound[vertex];
		while (id != -1) {
			removeEdge(id);
			id = nextInbound[id];
		}
	}

	private void initInbound() {
		if (firstInbound == null) {
			firstInbound = new int[firstOutbound.length];
			Arrays.fill(firstInbound, 0, vertexCount, -1);
			nextInbound = new int[from.length];
			for (int i = 0; i < edgeCount; i++) {
				nextInbound[i] = firstInbound[to[i]];
				firstInbound[to[i]] = i;
			}
		}
	}

	public final boolean flag(int id, int bit) {
		return (flags[id] >> bit & 1) != 0;
	}

	public final void setFlag(int id, int bit) {
		flags[id] |= 1 << bit;
	}

	public final void removeFlag(int id, int bit) {
		flags[id] &= -1 - (1 << bit);
	}

	public final void removeEdge(int id) {
		setFlag(id, REMOVED_BIT);
	}

	public final void restoreEdge(int id) {
		removeFlag(id, REMOVED_BIT);
	}

	public final boolean isRemoved(int id) {
		return flag(id, REMOVED_BIT);
	}

	public final Iterable<Edge> outbound(final int id) {
		initEdges();
		return new Iterable<Edge>() {
			public Iterator<Edge> iterator() {
				return new EdgeIterator(id, firstOutbound, nextOutbound);
			}
		};
	}

	public final Iterable<Edge> inbound(final int id) {
		initEdges();
		initInbound();
		return new Iterable<Edge>() {
			public Iterator<Edge> iterator() {
				return new EdgeIterator(id, firstInbound, nextInbound);
			}
		};
	}

	protected void ensureEdgeCapacity(int size) {
		if (from.length < size) {
			int newSize = Math.max(size, 2 * from.length);
			if (edges != null)
				edges = resize(edges, newSize);
			from = resize(from, newSize);
			to = resize(to, newSize);
			nextOutbound = resize(nextOutbound, newSize);
			if (nextInbound != null)
				nextInbound = resize(nextInbound, newSize);
			if (weight != null)
				weight = resize(weight, newSize);
			if (capacity != null)
				capacity = resize(capacity, newSize);
			if (reverseEdge != null)
				reverseEdge = resize(reverseEdge, newSize);
			flags = resize(flags, newSize);
		}
	}

	private void ensureVertexCapacity(int size) {
		if (firstOutbound.length < size) {
			int newSize = Math.max(size, 2 * from.length);
			firstOutbound = resize(firstOutbound, newSize);
			if (firstInbound != null)
				firstInbound = resize(firstInbound, newSize);
		}
	}

	protected final int[] resize(int[] array, int size) {
		int[] newArray = new int[size];
		System.arraycopy(array, 0, newArray, 0, array.length);
		return newArray;
	}

	private long[] resize(long[] array, int size) {
		long[] newArray = new long[size];
		System.arraycopy(array, 0, newArray, 0, array.length);
		return newArray;
	}

	private Edge[] resize(Edge[] array, int size) {
		Edge[] newArray = new Edge[size];
		System.arraycopy(array, 0, newArray, 0, array.length);
		return newArray;
	}

	public final boolean isSparse() {
		return vertexCount == 0 || edgeCount * 20 / vertexCount <= vertexCount;
	}

	protected class GraphEdge implements Edge {
		protected int id;

		protected GraphEdge(int id) {
			this.id = id;
		}

		public int getSource() {
			return source(id);
		}

		public int getDestination() {
			return destination(id);
		}

		public long getWeight() {
			return weight(id);
		}

		public long getCapacity() {
			return capacity(id);
		}

		public long getFlow() {
			return flow(id);
		}

		public void pushFlow(long flow) {
			Graph.this.pushFlow(id, flow);
		}

		public boolean getFlag(int bit) {
			return flag(id, bit);
		}

		public void setFlag(int bit) {
			Graph.this.setFlag(id, bit);
		}

		public void removeFlag(int bit) {
			Graph.this.removeFlag(id, bit);
		}

		public int getTransposedID() {
			return transposed(id);
		}

		public Edge getTransposedEdge() {
			int reverseID = getTransposedID();
			if (reverseID == -1)
				return null;
			initEdges();
			return edge(reverseID);
		}

		public int getReverseID() {
			return reverse(id);
		}

		public Edge getReverseEdge() {
			int reverseID = getReverseID();
			if (reverseID == -1)
				return null;
			initEdges();
			return edge(reverseID);
		}

		public int getID() {
			return id;
		}

		public void remove() {
			removeEdge(id);
		}

		public void restore() {
			restoreEdge(id);
		}
	}

	public class EdgeIterator implements Iterator<Edge> {
		private int edgeID;
		private final int[] next;
		private int lastID = -1;

		public EdgeIterator(int id, int[] first, int[] next) {
			this.next = next;
			edgeID = nextEdge(first[id]);
		}

		private int nextEdge(int id) {
			while (id != -1 && isRemoved(id))
				id = next[id];
			return id;
		}

		public boolean hasNext() {
			return edgeID != -1;
		}

		public Edge next() {
			if (edgeID == -1)
				throw new NoSuchElementException();
			lastID = edgeID;
			edgeID = nextEdge(next[lastID]);
			return edges[lastID];
		}

		public void remove() {
			if (lastID == -1)
				throw new IllegalStateException();
			removeEdge(lastID);
			lastID = -1;
		}
	}

}

class MiscUtils {
	public static final int[] DX4 = { 1, 0, -1, 0 };
	public static final int[] DY4 = { 0, -1, 0, 1 };
	public static final int[] DX8 = { 1, 1, 1, 0, -1, -1, -1, 0 };
	public static final int[] DY8 = { -1, 0, 1, 1, 1, 0, -1, -1 };
	public static final int[] DX_KNIGHT = { 2, 1, -1, -2, -2, -1, 1, 2 };
	public static final int[] DY_KNIGHT = { 1, 2, 2, 1, -1, -2, -2, -1 };

	private static final String[] ROMAN_TOKENS = { "M", "CM", "D", "CD", "C",
			"XC", "L", "XL", "X", "IX", "V", "IV", "I" };
	private static final int[] ROMAN_VALUES = { 1000, 900, 500, 400, 100, 90,
			50, 40, 10, 9, 5, 4, 1 };

	public static long josephProblem(long n, int k) {
		if (n == 1)
			return 0;
		if (k == 1)
			return n - 1;
		if (k > n)
			return (josephProblem(n - 1, k) + k) % n;
		long count = n / k;
		long result = josephProblem(n - count, k);
		result -= n % k;
		if (result < 0)
			result += n;
		else
			result += result / (k - 1);
		return result;
	}

	public static boolean isValidCell(int row, int column, int rowCount,
			int columnCount) {
		return row >= 0 && row < rowCount && column >= 0
				&& column < columnCount;
	}

	public static List<Integer> getPath(int[] last, int destination) {
		List<Integer> path = new ArrayList<Integer>();
		while (destination != -1) {
			path.add(destination);
			destination = last[destination];
		}
		inPlaceReverse(path);
		return path;
	}

	private static void inPlaceReverse(List<Integer> list) {
		for (int i = 0, j = list.size() - 1; i < j; i++, j--)
			swap(list, i, j);
	}

	private static void swap(List<Integer> list, int first, int second) {
		if (first == second)
			return;
		int temp = list.get(first);
		list.set(first, list.get(second));
		list.set(second, temp);
	}

	public static List<Integer> getPath(int[][] lastIndex,
			int[][] lastPathNumber, int destination, int pathNumber) {
		List<Integer> path = new ArrayList<Integer>();
		while (destination != -1 || pathNumber != 0) {
			path.add(destination);
			int nextDestination = lastIndex[destination][pathNumber];
			pathNumber = lastPathNumber[destination][pathNumber];
			destination = nextDestination;
		}
		inPlaceReverse(path);
		return path;
	}

	public static long maximalRectangleSum(long[][] array) {
		int n = array.length;
		int m = array[0].length;
		long[][] partialSums = new long[n + 1][m + 1];
		for (int i = 0; i < n; i++) {
			long rowSum = 0;
			for (int j = 0; j < m; j++) {
				rowSum += array[i][j];
				partialSums[i + 1][j + 1] = partialSums[i][j + 1] + rowSum;
			}
		}
		long result = Long.MIN_VALUE;
		for (int i = 0; i < m; i++) {
			for (int j = i; j < m; j++) {
				long minPartialSum = 0;
				for (int k = 1; k <= n; k++) {
					long current = partialSums[k][j + 1] - partialSums[k][i];
					result = Math.max(result, current - minPartialSum);
					minPartialSum = Math.min(minPartialSum, current);
				}
			}
		}
		return result;
	}

	public static int parseIP(String ip) {
		String[] components = ip.split("[.]");
		int result = 0;
		for (int i = 0; i < 4; i++)
			result += (1 << (24 - 8 * i)) * Integer.parseInt(components[i]);
		return result;
	}

	public static String buildIP(int mask) {
		StringBuilder result = new StringBuilder();
		for (int i = 0; i < 4; i++) {
			if (i != 0)
				result.append('.');
			result.append(mask >> (24 - 8 * i) & 255);
		}
		return result.toString();
	}

	public static long binarySearch(long from, long to,
			Function<Long, Boolean> function) {
		while (from < to) {
			long argument = from + (to - from) / 2;
			if (function.value(argument))
				to = argument;
			else
				from = argument + 1;
		}
		return from;
	}

	public static <T> boolean equals(T first, T second) {
		return first == null && second == null || first != null
				&& first.equals(second);
	}

	public static boolean isVowel(char ch) {
		ch = Character.toUpperCase(ch);
		return ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U'
				|| ch == 'Y';
	}

	public static boolean isStrictVowel(char ch) {
		ch = Character.toUpperCase(ch);
		return ch == 'A' || ch == 'E' || ch == 'I' || ch == 'O' || ch == 'U';
	}

	public static String convertToRoman(int number) {
		StringBuilder result = new StringBuilder();
		for (int i = 0; i < ROMAN_TOKENS.length; i++) {
			while (number >= ROMAN_VALUES[i]) {
				number -= ROMAN_VALUES[i];
				result.append(ROMAN_TOKENS[i]);
			}
		}
		return result.toString();
	}

	public static int convertFromRoman(String number) {
		int result = 0;
		for (int i = 0; i < ROMAN_TOKENS.length; i++) {
			while (number.startsWith(ROMAN_TOKENS[i])) {
				number = number.substring(ROMAN_TOKENS[i].length());
				result += ROMAN_VALUES[i];
			}
		}
		return result;
	}

	public static int distance(int x1, int y1, int x2, int y2) {
		int dx = x1 - x2;
		int dy = y1 - y2;
		return dx * dx + dy * dy;
	}

	public static <T extends Comparable<T>> T min(T first, T second) {
		if (first.compareTo(second) <= 0)
			return first;
		return second;
	}

	public static <T extends Comparable<T>> T max(T first, T second) {
		if (first.compareTo(second) <= 0)
			return second;
		return first;
	}

	public static void decreaseByOne(int[]... arrays) {
		for (int[] array : arrays) {
			for (int i = 0; i < array.length; i++)
				array[i]--;
		}
	}

	public static int[] getIntArray(String s) {
		String[] tokens = s.split(" ");
		int[] result = new int[tokens.length];
		for (int i = 0; i < result.length; i++)
			result[i] = Integer.parseInt(tokens[i]);
		return result;
	}
}

class IntegerUtils {
	public static long gcd(long a, long b) {
		a = Math.abs(a);
		b = Math.abs(b);
		while (b != 0) {
			long temp = a % b;
			a = b;
			b = temp;
		}
		return a;
	}

	public static int gcd(int a, int b) {
		a = Math.abs(a);
		b = Math.abs(b);
		while (b != 0) {
			int temp = a % b;
			a = b;
			b = temp;
		}
		return a;
	}

	public static int[] generatePrimes(int upTo) {
		int[] isPrime = generateBitPrimalityTable(upTo);
		List<Integer> primes = new ArrayList<Integer>();
		for (int i = 0; i < upTo; i++) {
			if ((isPrime[i >> 5] >>> (i & 31) & 1) == 1)
				primes.add(i);
		}
		int[] array = new int[primes.size()];
		for (int i = 0; i < array.length; i++)
			array[i] = primes.get(i);
		return array;
	}

	public static boolean[] generatePrimalityTable(int upTo) {
		boolean[] isPrime = new boolean[upTo];
		if (upTo < 2)
			return isPrime;
		Arrays.fill(isPrime, true);
		isPrime[0] = isPrime[1] = false;
		for (int i = 2; i * i < upTo; i++) {
			if (isPrime[i]) {
				for (int j = i * i; j < upTo; j += i)
					isPrime[j] = false;
			}
		}
		return isPrime;
	}

	public static int[] generateBitPrimalityTable(int upTo) {
		int[] isPrime = new int[(upTo + 31) >> 5];
		if (upTo < 2)
			return isPrime;
		Arrays.fill(isPrime, -1);
		isPrime[0] &= -4;
		for (int i = 2; i * i < upTo; i++) {
			if ((isPrime[i >> 5] >>> (i & 31) & 1) == 1) {
				for (int j = i * i; j < upTo; j += i)
					isPrime[j >> 5] &= -1 - (1 << (j & 31));
			}
		}
		return isPrime;
	}

	public static int[] generateDivisorTable(int upTo) {
		int[] divisor = new int[upTo];
		for (int i = 1; i < upTo; i++)
			divisor[i] = i;
		for (int i = 2; i * i < upTo; i++) {
			if (divisor[i] == i) {
				for (int j = i * i; j < upTo; j += i)
					divisor[j] = i;
			}
		}
		return divisor;
	}

	public static long powerInFactorial(long n, long p) {
		long result = 0;
		while (n != 0) {
			result += n /= p;
		}
		return result;
	}

	public static int sumDigits(CharSequence number) {
		int result = 0;
		for (int i = number.length() - 1; i >= 0; i--)
			result += digitValue(number.charAt(i));
		return result;
	}

	public static int digitValue(char digit) {
		if (Character.isDigit(digit))
			return digit - '0';
		if (Character.isUpperCase(digit))
			return digit + 10 - 'A';
		return digit + 10 - 'a';
	}

	public static int longCompare(long a, long b) {
		if (a < b)
			return -1;
		if (a > b)
			return 1;
		return 0;
	}

	public static long[][] generateBinomialCoefficients(int n) {
		long[][] result = new long[n + 1][n + 1];
		for (int i = 0; i <= n; i++) {
			result[i][0] = 1;
			for (int j = 1; j <= i; j++)
				result[i][j] = result[i - 1][j - 1] + result[i - 1][j];
		}
		return result;
	}

	public static long[][] generateBinomialCoefficients(int n, long module) {
		long[][] result = new long[n + 1][n + 1];
		if (module == 1)
			return result;
		for (int i = 0; i <= n; i++) {
			result[i][0] = 1;
			for (int j = 1; j <= i; j++) {
				result[i][j] = result[i - 1][j - 1] + result[i - 1][j];
				if (result[i][j] >= module)
					result[i][j] -= module;
			}
		}
		return result;
	}

	public static long[] generateBinomialRow(int n, long module) {
		long[] result = generateReverse(n + 1, module);
		result[0] = 1;
		for (int i = 1; i <= n; i++)
			result[i] = result[i - 1] * (n - i + 1) % module * result[i]
					% module;
		return result;
	}

	public static int[] representationInBase(long number, int base) {
		long basePower = base;
		int exponent = 1;
		while (number >= basePower) {
			basePower *= base;
			exponent++;
		}
		int[] representation = new int[exponent];
		for (int i = 0; i < exponent; i++) {
			basePower /= base;
			representation[i] = (int) (number / basePower);
			number %= basePower;
		}
		return representation;
	}

	public static int trueDivide(int a, int b) {
		return (a - trueMod(a, b)) / b;
	}

	public static long trueDivide(long a, long b) {
		return (a - trueMod(a, b)) / b;
	}

	public static int trueMod(int a, int b) {
		a %= b;
		a += b;
		a %= b;
		return a;
	}

	public static long trueMod(long a, long b) {
		a %= b;
		a += b;
		a %= b;
		return a;
	}

	public static long factorial(int n) {
		long result = 1;
		for (int i = 2; i <= n; i++)
			result *= i;
		return result;
	}

	public static long factorial(int n, long mod) {
		long result = 1;
		for (int i = 2; i <= n; i++)
			result = result * i % mod;
		return result % mod;
	}

	public static List<Pair<Long, Integer>> factorize(long number) {
		List<Pair<Long, Integer>> result = new ArrayList<Pair<Long, Integer>>();
		for (long i = 2; i * i <= number; i++) {
			if (number % i == 0) {
				int power = 0;
				do {
					power++;
					number /= i;
				} while (number % i == 0);
				result.add(Pair.makePair(i, power));
			}
		}
		if (number != 1)
			result.add(Pair.makePair(number, 1));
		return result;
	}

	public static List<Long> getDivisors(long number) {
		List<Pair<Long, Integer>> primeDivisors = factorize(number);
		return getDivisorsImpl(primeDivisors, 0, 1, new ArrayList<Long>());
	}

	private static List<Long> getDivisorsImpl(
			List<Pair<Long, Integer>> primeDivisors, int index, long current,
			List<Long> result) {
		if (index == primeDivisors.size()) {
			result.add(current);
			return result;
		}
		long p = primeDivisors.get(index).first;
		int power = primeDivisors.get(index).second;
		for (int i = 0; i <= power; i++) {
			getDivisorsImpl(primeDivisors, index + 1, current, result);
			current *= p;
		}
		return result;
	}

	public static long power(long base, long exponent) {
		if (exponent == 0)
			return 1;
		long result = power(base, exponent >> 1);
		result = result * result;
		if ((exponent & 1) != 0)
			result = result * base;
		return result;
	}

	public static long power(long base, long exponent, long mod) {
		if (base >= mod)
			base %= mod;
		if (exponent == 0)
			return 1 % mod;
		long result = power(base, exponent >> 1, mod);
		result = result * result % mod;
		if ((exponent & 1) != 0)
			result = result * base % mod;
		return result;
	}

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

	public static long[] generateFibonacci(long upTo) {
		int count = 0;
		long last = 0;
		long current = 1;
		while (current <= upTo) {
			long next = last + current;
			last = current;
			current = next;
			count++;
		}
		return generateFibonacci(count, -1);
	}

	public static long[] generateFibonacci(int count, long module) {
		long[] result = new long[count];
		if (module == -1) {
			if (count != 0)
				result[0] = 1;
			if (count > 1)
				result[1] = 1;
			for (int i = 2; i < count; i++)
				result[i] = result[i - 1] + result[i - 2];
		} else {
			if (count != 0)
				result[0] = 1 % module;
			if (count > 1)
				result[1] = 1 % module;
			for (int i = 2; i < count; i++)
				result[i] = (result[i - 1] + result[i - 2]) % module;
		}
		return result;
	}

	public static long[] generateHappy(int digits) {
		long[] happy = new long[(1 << (digits + 1)) - 2];
		happy[0] = 4;
		happy[1] = 7;
		int first = 0;
		int last = 2;
		for (int i = 2; i <= digits; i++) {
			for (int j = 0; j < last - first; j++) {
				happy[last + 2 * j] = 10 * happy[first + j] + 4;
				happy[last + 2 * j + 1] = 10 * happy[first + j] + 7;
			}
			int next = last + 2 * (last - first);
			first = last;
			last = next;
		}
		return happy;
	}

	public static long[] generateFactorial(int count, long module) {
		long[] result = new long[count];
		if (module == -1) {
			if (count != 0)
				result[0] = 1;
			for (int i = 1; i < count; i++)
				result[i] = result[i - 1] * i;
		} else {
			if (count != 0)
				result[0] = 1 % module;
			for (int i = 1; i < count; i++)
				result[i] = (result[i - 1] * i) % module;
		}
		return result;
	}

	public static long reverse(long number, long module) {
		return power(number, module - 2, module);
	}

	public static boolean isPrime(long number) {
		if (number < 2)
			return false;
		for (long i = 2; i * i <= number; i++) {
			if (number % i == 0)
				return false;
		}
		return true;
	}

	public static long[] generateReverse(int upTo, long module) {
		long[] result = new long[upTo];
		if (upTo > 1)
			result[1] = 1;
		for (int i = 2; i < upTo; i++)
			result[i] = (module - module / i * result[((int) (module % i))]
					% module)
					% module;
		return result;
	}

	public static long[] generateReverseFactorials(int upTo, long module) {
		long[] result = generateReverse(upTo, module);
		if (upTo > 0)
			result[0] = 1;
		for (int i = 1; i < upTo; i++)
			result[i] = result[i] * result[i - 1] % module;
		return result;
	}

	public static long[] generatePowers(long base, int count, long mod) {
		long[] result = new long[count];
		if (count != 0)
			result[0] = 1 % mod;
		for (int i = 1; i < count; i++)
			result[i] = result[i - 1] * base % mod;
		return result;
	}

	public static long nextPrime(long from) {
		if (from <= 2)
			return 2;
		from += 1 - (from & 1);
		while (!isPrime(from))
			from += 2;
		return from;
	}

	public static long binomialCoefficient(int n, int m, long mod) {
		if (m < 0 || m > n)
			return 0;
		if (2 * m > n)
			m = n - m;
		long result = 1;
		for (int i = n - m + 1; i <= n; i++)
			result = result * i % mod;
		return result
				* BigInteger.valueOf(factorial(m, mod))
						.modInverse(BigInteger.valueOf(mod)).longValue() % mod;
	}

	public static boolean isSquare(long number) {
		long sqrt = Math.round(Math.sqrt(number));
		return sqrt * sqrt == number;
	}

	public static long findCommon(long aRemainder, long aMod, long bRemainder,
			long bMod) {
		long modGCD = gcd(aMod, bMod);
		long gcdRemainder = aRemainder % modGCD;
		if (gcdRemainder != bRemainder % modGCD)
			return -1;
		aMod /= modGCD;
		aRemainder /= modGCD;
		bMod /= modGCD;
		bRemainder /= modGCD;
		long aReverse = BigInteger.valueOf(aMod)
				.modInverse(BigInteger.valueOf(bMod)).longValue();
		long bReverse = BigInteger.valueOf(bMod)
				.modInverse(BigInteger.valueOf(aMod)).longValue();
		long mod = aMod * bMod;
		return (bReverse * aRemainder % mod * bMod + aReverse * bRemainder
				% mod * aMod)
				% mod * modGCD + gcdRemainder;
	}

	public static long[] generatePowers(long base, long maxValue) {
		if (maxValue <= 0)
			return new long[0];
		int size = 1;
		long current = 1;
		while (maxValue / base >= current) {
			current *= base;
			size++;
		}
		return generatePowers(base, size, Long.MAX_VALUE);
	}
}

interface IntComparator extends Comparator<Integer> {
	public static final IntComparator DEFAULT = new IntComparator() {
		public int compare(Integer first, Integer second) {
			if (first < second)
				return -1;
			if (first > second)
				return 1;
			return 0;
		}
	};

	public static final IntComparator REVERSE = new IntComparator() {
		public int compare(Integer first, Integer second) {
			if (first < second)
				return 1;
			if (first > second)
				return -1;
			return 0;
		}
	};

	public int compare(Integer first, Integer second);
}

class BidirectionalGraph extends Graph {
	public int[] transposedEdge;

	public BidirectionalGraph(int vertexCount) {
		this(vertexCount, vertexCount);
	}

	public BidirectionalGraph(int vertexCount, int edgeCapacity) {
		super(vertexCount, 2 * edgeCapacity);
		transposedEdge = new int[2 * edgeCapacity];
	}

	public static BidirectionalGraph createGraph(int vertexCount, int[] from,
			int[] to) {
		BidirectionalGraph graph = new BidirectionalGraph(vertexCount,
				from.length);
		for (int i = 0; i < from.length; i++)
			graph.addSimpleEdge(from[i], to[i]);
		return graph;
	}

	public static BidirectionalGraph createWeightedGraph(int vertexCount,
			int[] from, int[] to, long[] weight) {
		BidirectionalGraph graph = new BidirectionalGraph(vertexCount,
				from.length);
		for (int i = 0; i < from.length; i++)
			graph.addWeightedEdge(from[i], to[i], weight[i]);
		return graph;
	}

	public static BidirectionalGraph createFlowGraph(int vertexCount,
			int[] from, int[] to, long[] capacity) {
		BidirectionalGraph graph = new BidirectionalGraph(vertexCount,
				from.length * 2);
		for (int i = 0; i < from.length; i++)
			graph.addFlowEdge(from[i], to[i], capacity[i]);
		return graph;
	}

	public static BidirectionalGraph createFlowWeightedGraph(int vertexCount,
			int[] from, int[] to, long[] weight, long[] capacity) {
		BidirectionalGraph graph = new BidirectionalGraph(vertexCount,
				from.length * 2);
		for (int i = 0; i < from.length; i++)
			graph.addFlowWeightedEdge(from[i], to[i], weight[i], capacity[i]);
		return graph;
	}

	@Override
	public int addEdge(int fromID, int toID, long weight, long capacity,
			int reverseEdge) {
		int lastEdgeCount = edgeCount;
		super.addEdge(fromID, toID, weight, capacity, reverseEdge);
		super.addEdge(toID, fromID, weight, capacity, reverseEdge == -1 ? -1
				: reverseEdge + 1);
		this.transposedEdge[lastEdgeCount] = lastEdgeCount + 1;
		this.transposedEdge[lastEdgeCount + 1] = lastEdgeCount;
		return lastEdgeCount;
	}

	@Override
	protected int entriesPerEdge() {
		return 2;
	}

	@Override
	public final int transposed(int id) {
		return transposedEdge[id];
	}

	@Override
	protected void ensureEdgeCapacity(int size) {
		if (size > edgeCapacity()) {
			super.ensureEdgeCapacity(size);
			transposedEdge = resize(transposedEdge, edgeCapacity());
		}
	}
}

class Pair<U, V> implements Comparable<Pair<U, V>> {
	public final U first;
	public final V second;

	public static <U, V> Pair<U, V> makePair(U first, V second) {
		return new Pair<U, V>(first, second);
	}

	private Pair(U first, V second) {
		this.first = first;
		this.second = second;
	}

	@Override
	public boolean equals(Object o) {
		if (this == o)
			return true;
		if (o == null || getClass() != o.getClass())
			return false;

		Pair pair = (Pair) o;

		return !(first != null ? !first.equals(pair.first) : pair.first != null)
				&& !(second != null ? !second.equals(pair.second)
						: pair.second != null);

	}

	@Override
	public int hashCode() {
		int result = first != null ? first.hashCode() : 0;
		result = 31 * result + (second != null ? second.hashCode() : 0);
		return result;
	}

	public Pair<V, U> swap() {
		return makePair(second, first);
	}

	@Override
	public String toString() {
		return "(" + first + "," + second + ")";
	}

	@SuppressWarnings({ "unchecked" })
	public int compareTo(Pair<U, V> o) {
		int value = ((Comparable<U>) first).compareTo(o.first);
		if (value != 0)
			return value;
		return ((Comparable<V>) second).compareTo(o.second);
	}
}

interface Edge {
	public int getSource();

	public int getDestination();

	public long getWeight();

	public long getCapacity();

	public long getFlow();

	public void pushFlow(long flow);

	public boolean getFlag(int bit);

	public void setFlag(int bit);

	public void removeFlag(int bit);

	public int getTransposedID();

	public Edge getTransposedEdge();

	public int getReverseID();

	public Edge getReverseEdge();

	public int getID();

	public void remove();

	public void restore();
}

interface Function<A, V> {
	public abstract V value(A argument);
}