Problem: Dreamoon likes to play with sets, integers and <image>. <image> is defined as the largest positive integer that divides both a and b.

Let S be a set of exactly four distinct integers greater than 0. Define S to be of rank k if and only if for all pairs of distinct elements si, sj from S, <image>.

Given k and n, Dreamoon wants to make up n sets of rank k using integers from 1 to m such that no integer is used in two different sets (of course you can leave some integers without use). Calculate the minimum m that makes it possible and print one possible solution.

Input

The single line of the input contains two space separated integers n, k (1 ≤ n ≤ 10 000, 1 ≤ k ≤ 100).

Output

On the first line print a single integer — the minimal possible m. 

On each of the next n lines print four space separated integers representing the i-th set.

Neither the order of the sets nor the order of integers within a set is important. If there are multiple possible solutions with minimal m, print any one of them.

Examples

Input

1 1


Output

5
1 2 3 5


Input

2 2


Output

22
2 4 6 22
14 18 10 16

Note

For the first example it's easy to see that set {1, 2, 3, 4} isn't a valid set of rank 1 since <image>.

Solution (in JAVA):

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

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 Task();
		solver.solve(1, in, out);
		out.close();
	}
}

class Task {
	
	public void solve(int testNumber, InputReader in, OutputWriter out) {
		int n=in.readInt(), k=in.readInt();
		out.printLine((6*n-1)*k);
		for (int i=0; i<n; i++) out.printLine((6*i+1)*k, k*(6*i+2), k*(6*i+3), k*(6*i+5));
	}
}

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(IntCollection collection) {
		boolean first = true;
		for (IntIterator iterator = collection.iterator(); iterator.isValid(); iterator
				.advance()) {
			if (first)
				first = false;
			else
				writer.print(' ');
			writer.print(iterator.value());
		}
	}

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

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

	public void printLine(IntCollection 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 ArrayUtils {
	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 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 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 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) {
		if (from == 0 && to == array.length)
			new IntArray(array).inPlaceSort(comparator);
		else
			new IntArray(array).subList(from, to).inPlaceSort(comparator);
		return array;
	}

	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[] 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;
		}
	}

	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 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 new IntArray(array).nextPermutation();
	}

	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(int first, int 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;
	}
}

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 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;
		}
	}

}

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

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 IntList getPath(int[] last, int destination) {
		IntList path = new IntArrayList();
		while (destination != -1) {
			path.add(destination);
			destination = last[destination];
		}
		path.inPlaceReverse();
		return path;
	}

	public static IntList getPath(int[][] lastIndex, int[][] lastPathNumber,
			int destination, int pathNumber) {
		IntList path = new IntArrayList();
		while (destination != -1 || pathNumber != 0) {
			path.add(destination);
			int nextDestination = lastIndex[destination][pathNumber];
			pathNumber = lastPathNumber[destination][pathNumber];
			destination = nextDestination;
		}
		path.inPlaceReverse();
		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;
	}
}

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();
}

class IntArrayList extends IntList {
	private int[] array;
	private int size;

	public IntArrayList() {
		this(10);
	}

	public IntArrayList(int capacity) {
		array = new int[capacity];
	}

	public IntArrayList(IntList list) {
		this(list.size());
		addAll(list);
	}

	@Override
	public int get(int index) {
		if (index >= size)
			throw new IndexOutOfBoundsException();
		return array[index];
	}

	@Override
	public void set(int index, int value) {
		if (index >= size)
			throw new IndexOutOfBoundsException();
		array[index] = value;
	}

	@Override
	public int size() {
		return size;
	}

	@Override
	public void add(int value) {
		ensureCapacity(size + 1);
		array[size++] = value;
	}

	public void ensureCapacity(int newCapacity) {
		if (newCapacity > array.length) {
			int[] newArray = new int[Math.max(newCapacity, array.length << 1)];
			System.arraycopy(array, 0, newArray, 0, size);
			array = newArray;
		}
	}

	@Override
	public int[] toArray() {
		int[] array = new int[size];
		System.arraycopy(this.array, 0, array, 0, size);
		return array;
	}

	@Override
	public int popBack() {
		return array[--size];
	}
}

class IntArray extends IntList {
	private final int[] array;

	public IntArray(int[] array) {
		this.array = array;
	}

	public IntArray(IntCollection collection) {
		array = new int[collection.size()];
		int i = 0;
		for (IntIterator iterator = collection.iterator(); iterator.isValid(); iterator
				.advance())
			array[i++] = iterator.value();
	}

	@Override
	public int get(int index) {
		return array[index];
	}

	@Override
	public void set(int index, int value) {
		array[index] = value;
	}

	@Override
	public int size() {
		return array.length;
	}

	@Override
	public void add(int value) {
		throw new UnsupportedOperationException();
	}

	@Override
	public int[] toArray() {
		return array;
	}
}

abstract class IntList extends IntCollection implements Comparable<IntList> {
	private static final int INSERTION_THRESHOLD = 16;
	private static IntList EMPTY_LIST;

	public abstract int get(int index);

	public abstract void set(int index, int value);

	@Override
	public IntIterator iterator() {
		return new IntIterator() {
			private int size = size();
			private int index = 0;

			public int value() throws NoSuchElementException {
				if (!isValid())
					throw new NoSuchElementException();
				return get(index);
			}

			public void advance() throws NoSuchElementException {
				if (!isValid())
					throw new NoSuchElementException();
				index++;
			}

			public boolean isValid() {
				return index < size;
			}
		};
	}

	@Override
	public void remove(int value) {
		throw new UnsupportedOperationException();
	}

	public int find(int value) {
		int size = size();
		for (int i = 0; i < size; i++) {
			if (get(i) == value)
				return i;
		}
		return -1;
	}

	public int findLast(int value) {
		int size = size();
		for (int i = size - 1; i >= 0; i--) {
			if (get(i) == value)
				return i;
		}
		return -1;
	}

	public boolean nextPermutation() {
		return nextPermutation(IntComparator.DEFAULT);
	}

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

	public void inPlaceReverse() {
		for (int i = 0, j = size() - 1; i < j; i++, j--)
			swap(i, j);
	}

	public IntList subList(final int from, final int to) {
		return new SubList(from, to);
	}

	private void swap(int first, int second) {
		if (first == second)
			return;
		int temp = get(first);
		set(first, get(second));
		set(second, temp);
	}

	public IntSortedList inPlaceSort() {
		return inPlaceSort(IntComparator.DEFAULT);
	}

	public IntSortedList inPlaceSort(IntComparator comparator) {
		quickSort(0, size() - 1,
				(Integer.bitCount(Integer.highestOneBit(size()) - 1) * 5) >> 1,
				comparator);
		return new IntSortedArray(this, comparator);
	}

	private void quickSort(int from, int to, int remaining,
			IntComparator comparator) {
		if (to - from < INSERTION_THRESHOLD) {
			insertionSort(from, to, comparator);
			return;
		}
		if (remaining == 0) {
			heapSort(from, to, comparator);
			return;
		}
		remaining--;
		int pivotIndex = (from + to) >> 1;
		int pivot = get(pivotIndex);
		swap(pivotIndex, to);
		int storeIndex = from;
		int equalIndex = to;
		for (int i = from; i < equalIndex; i++) {
			int value = comparator.compare(get(i), pivot);
			if (value < 0)
				swap(storeIndex++, i);
			else if (value == 0)
				swap(--equalIndex, i--);
		}
		quickSort(from, storeIndex - 1, remaining, comparator);
		for (int i = equalIndex; i <= to; i++)
			swap(storeIndex++, i);
		quickSort(storeIndex, to, remaining, comparator);
	}

	private void heapSort(int from, int to, IntComparator comparator) {
		for (int i = (to + from - 1) >> 1; i >= from; i--)
			siftDown(i, to, comparator, from);
		for (int i = to; i > from; i--) {
			swap(from, i);
			siftDown(from, i - 1, comparator, from);
		}
	}

	private void siftDown(int start, int end, IntComparator comparator,
			int delta) {
		int value = get(start);
		while (true) {
			int child = ((start - delta) << 1) + 1 + delta;
			if (child > end)
				return;
			int childValue = get(child);
			if (child + 1 <= end) {
				int otherValue = get(child + 1);
				if (comparator.compare(otherValue, childValue) > 0) {
					child++;
					childValue = otherValue;
				}
			}
			if (comparator.compare(value, childValue) >= 0)
				return;
			swap(start, child);
			start = child;
		}
	}

	private void insertionSort(int from, int to, IntComparator comparator) {
		for (int i = from + 1; i <= to; i++) {
			int value = get(i);
			for (int j = i - 1; j >= from; j--) {
				if (comparator.compare(get(j), value) <= 0)
					break;
				swap(j, j + 1);
			}
		}
	}

	public IntSortedList sort() {
		return sort(IntComparator.DEFAULT);
	}

	public IntSortedList sort(IntComparator comparator) {
		return new IntArray(this).inPlaceSort(comparator);
	}

	public int back() {
		return get(size() - 1);
	}

	public int popBack() {
		throw new UnsupportedOperationException();
	}

	public int hashCode() {
		int hashCode = 1;
		for (IntIterator i = iterator(); i.isValid(); i.advance())
			hashCode = 31 * hashCode + i.value();
		return hashCode;
	}

	@Override
	public boolean equals(Object obj) {
		if (!(obj instanceof IntList))
			return false;
		IntList list = (IntList) obj;
		if (list.size() != size())
			return false;
		IntIterator i = iterator();
		IntIterator j = list.iterator();
		while (i.isValid()) {
			if (i.value() != j.value())
				return false;
			i.advance();
			j.advance();
		}
		return true;
	}

	public int compareTo(IntList o) {
		IntIterator i = iterator();
		IntIterator j = o.iterator();
		while (true) {
			if (i.isValid()) {
				if (j.isValid()) {
					if (i.value() != j.value()) {
						if (i.value() < j.value())
							return -1;
						else
							return 1;
					}
				} else
					return 1;
			} else {
				if (j.isValid())
					return -1;
				else
					return 0;
			}
			i.advance();
			j.advance();
		}
	}

	public static IntList emptyList() {
		if (EMPTY_LIST == null)
			EMPTY_LIST = new IntArray(new int[0]);
		return EMPTY_LIST;
	}

	private class SubList extends IntList {
		private final int to;
		private final int from;
		private int size;

		public SubList(int from, int to) {
			this.to = to;
			this.from = from;
			size = to - from;
		}

		@Override
		public int get(int index) {
			if (index < 0 || index >= size)
				throw new IndexOutOfBoundsException();
			return IntList.this.get(index + from);
		}

		@Override
		public void set(int index, int value) {
			if (index < 0 || index >= size)
				throw new IndexOutOfBoundsException();
			IntList.this.set(index + from, value);
		}

		@Override
		public int size() {
			return size;
		}

		@Override
		public void add(int value) {
			throw new UnsupportedOperationException();
		}
	}
}

abstract class IntCollection {
	public abstract IntIterator iterator();

	public abstract int size();

	public abstract void add(int value);

	public abstract void remove(int value);

	public void forEach(IntTask task) {
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance())
			task.process(iterator.value());
	}

	public boolean contains(int value) {
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance()) {
			if (iterator.value() == value)
				return true;
		}
		return false;
	}

	public int count(int value) {
		int result = 0;
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance()) {
			if (iterator.value() == value)
				result++;
		}
		return result;
	}

	public int min() {
		if (size() == 0)
			throw new NoSuchElementException();
		int result = Integer.MAX_VALUE;
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance())
			result = Math.min(result, iterator.value());
		return result;
	}

	public int max() {
		if (size() == 0)
			throw new NoSuchElementException();
		int result = Integer.MIN_VALUE;
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance())
			result = Math.max(result, iterator.value());
		return result;
	}

	public IntCollection union(final IntCollection other) {
		return new IntCollection() {
			@Override
			public IntIterator iterator() {
				return new IntIterator() {
					private IntIterator first = IntCollection.this.iterator();
					private IntIterator second;

					public int value() throws NoSuchElementException {
						if (first.isValid())
							return first.value();
						return second.value();
					}

					public void advance() throws NoSuchElementException {
						if (first.isValid()) {
							first.advance();
							if (!first.isValid())
								second = other.iterator();
						} else
							second.advance();
					}

					public boolean isValid() {
						return first.isValid() || second.isValid();
					}
				};
			}

			@Override
			public int size() {
				return IntCollection.this.size() + other.size();
			}

			@Override
			public void add(int value) {
				throw new UnsupportedOperationException();
			}

			@Override
			public void remove(int value) {
				throw new UnsupportedOperationException();
			}
		};
	}

	public IntCollection map(final IntFunction function) {
		return new IntCollection() {
			@Override
			public IntIterator iterator() {
				return new IntIterator() {
					private IntIterator iterator = IntCollection.this
							.iterator();

					public int value() throws NoSuchElementException {
						return function.value(iterator.value());
					}

					public void advance() throws NoSuchElementException {
						iterator().advance();
					}

					public boolean isValid() {
						return iterator().isValid();
					}
				};
			}

			@Override
			public int size() {
				return IntCollection.this.size();
			}

			@Override
			public void add(int value) {
				throw new UnsupportedOperationException();
			}

			@Override
			public void remove(int value) {
				throw new UnsupportedOperationException();
			}
		};
	}

	public int[] toArray() {
		int size = size();
		int[] array = new int[size];
		int i = 0;
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance())
			array[i++] = iterator.value();
		return array;
	}

	public long sum() {
		long result = 0;
		for (IntIterator iterator = iterator(); iterator.isValid(); iterator
				.advance())
			result += iterator.value();
		return result;
	}

	public void addAll(IntCollection values) {
		for (IntIterator it = values.iterator(); it.isValid(); it.advance()) {
			add(it.value());
		}
	}

	public void removeAll(IntCollection values) {
		for (IntIterator it = values.iterator(); it.isValid(); it.advance()) {
			remove(it.value());
		}
	}

	public void retainAll(IntCollection values) {
		for (IntIterator it = iterator(); it.isValid(); it.advance()) {
			if (!values.contains(it.value())) {
				remove(it.value());
			}
		}
	}
}

interface IntIterator {
	public int value() throws NoSuchElementException;

	/*
	 * @throws NoSuchElementException only if iterator already invalid
	 */
	public void advance() throws NoSuchElementException;

	public boolean isValid();
}

abstract class IntSortedList extends IntList {
	protected final IntComparator comparator;

	protected IntSortedList(IntComparator comparator) {
		this.comparator = comparator;
	}

	@Override
	public void set(int index, int value) {
		throw new UnsupportedOperationException();
	}

	@Override
	public void add(int value) {
		throw new UnsupportedOperationException();
	}

	@Override
	public IntSortedList inPlaceSort(IntComparator comparator) {
		if (comparator == this.comparator)
			return this;
		throw new UnsupportedOperationException();
	}

	@Override
	public boolean contains(int value) {
		int index = lowerBound(value);
		return index != size() && get(index) == value;
	}

	public int lowerBound(int value) {
		int left = 0;
		int right = size();
		while (left < right) {
			int middle = (left + right) >> 1;
			if (comparator.compare(get(middle), value) >= 0)
				right = middle;
			else
				left = middle + 1;
		}
		return left;
	}

	public int upperBound(int value) {
		int left = 0;
		int right = size();
		while (left < right) {
			int middle = (left + right) >> 1;
			if (comparator.compare(get(middle), value) > 0)
				right = middle;
			else
				left = middle + 1;
		}
		return left;
	}

	protected void ensureSorted() {
		int size = size();
		if (size == 0)
			return;
		int last = get(0);
		for (int i = 1; i < size; i++) {
			int current = get(i);
			if (comparator.compare(last, current) > 0)
				throw new IllegalArgumentException();
			last = current;
		}
	}

	@Override
	public IntSortedList subList(final int from, final int to) {
		return new IntSortedList(comparator) {
			private int size = to - from;

			@Override
			public int get(int index) {
				if (index < 0 || index >= size)
					throw new IndexOutOfBoundsException();
				return IntSortedList.this.get(index + from);
			}

			@Override
			public int size() {
				return size;
			}
		};
	}
}

class IntSortedArray extends IntSortedList {
	private final int[] array;

	public IntSortedArray(int[] array) {
		this(array, IntComparator.DEFAULT);
	}

	public IntSortedArray(IntCollection collection) {
		this(collection, IntComparator.DEFAULT);
	}

	public IntSortedArray(int[] array, IntComparator comparator) {
		super(comparator);
		this.array = array;
		ensureSorted();
	}

	public IntSortedArray(IntCollection collection, IntComparator comparator) {
		super(comparator);
		array = new int[collection.size()];
		int i = 0;
		for (IntIterator iterator = collection.iterator(); iterator.isValid(); iterator
				.advance())
			array[i++] = iterator.value();
		ensureSorted();
	}

	@Override
	public int get(int index) {
		return array[index];
	}

	@Override
	public int size() {
		return array.length;
	}
}

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

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

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

interface IntTask {
	public void process(int value);
}

interface IntFunction {
	public int value(int key);
}

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);
		IntList primes = new IntArrayList();
		for (int i = 0; i < upTo; i++) {
			if ((isPrime[i >> 5] >>> (i & 31) & 1) == 1)
				primes.add(i);
		}
		return primes.toArray();
	}

	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);
	}
}

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 IndependentSetSystem {
	public boolean join(int first, int second);

	public int get(int index);

	public int getSetCount();

	public void setListener(Listener listener);

	public static interface Listener {
		public void joined(int joinedRoot, int root);
	}
}

class RecursiveIndependentSetSystem implements IndependentSetSystem {
	private final int[] color;
	private final int[] rank;
	private int setCount;
	private Listener listener;

	public RecursiveIndependentSetSystem(int size) {
		color = new int[size];
		rank = new int[size];
		for (int i = 0; i < size; i++)
			color[i] = i;
		setCount = size;
	}

	public RecursiveIndependentSetSystem(RecursiveIndependentSetSystem other) {
		color = other.color.clone();
		rank = other.rank.clone();
		setCount = other.setCount;
	}

	public boolean join(int first, int second) {
		first = get(first);
		second = get(second);
		if (first == second)
			return false;
		if (rank[first] < rank[second]) {
			int temp = first;
			first = second;
			second = temp;
		} else if (rank[first] == rank[second])
			rank[first]++;
		setCount--;
		color[second] = first;
		if (listener != null)
			listener.joined(second, first);
		return true;
	}

	public int get(int index) {
		if (color[index] == index)
			return index;
		return color[index] = get(color[index]);
	}

	public int getSetCount() {
		return setCount;
	}

	public void setListener(Listener listener) {
		this.listener = listener;
	}
}