The Little Elephant has array a, consisting of n positive integers, indexed from 1 to n. Let's denote the number with index i as ai.

The Little Elephant wants to count, how many pairs of integers l and r are there, such that 1 ≤ l < r ≤ n and sequence b = a1a2... alarar + 1... an has no more than k inversions. 

An inversion in sequence b is a pair of elements of the sequence b, that change their relative order after a stable sorting of the sequence. In other words, an inversion is a pair of integers i and j, such that 1 ≤ i < j ≤ |b| and bi > bj, where |b| is the length of sequence b, and bj is its j-th element.

Help the Little Elephant and count the number of the described pairs.

Input

The first line contains two integers n and k (2 ≤ n ≤ 105, 0 ≤ k ≤ 1018) — the size of array a and the maximum allowed number of inversions respectively. The next line contains n positive integers, separated by single spaces, a1, a2, ..., an (1 ≤ ai ≤ 109) — elements of array a.

Please, do not use the %lld specifier to read or write 64-bit integers in С++. It is preferred to use cin, cout streams or the %I64d specifier.

Output

In a single line print a single number — the answer to the problem.

Examples

Input

3 1
1 3 2


Output

3


Input

5 2
1 3 2 1 7


Output

6
import java.util.NavigableSet;
import java.io.OutputStreamWriter;
import java.io.BufferedWriter;
import java.util.SortedSet;
import java.util.Comparator;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Random;
import java.io.Writer;
import java.util.Collection;
import java.util.List;
import java.io.IOException;
import java.util.InputMismatchException;
import java.util.ArrayList;
import java.util.Set;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.math.BigInteger;
import java.util.Collections;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 * @author Egor Kulikov (egor@egork.net)
 */
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);
		TaskE solver = new TaskE();
		solver.solve(1, in, out);
		out.close();
	}
}

class TaskE {
	public void solve(int testNumber, InputReader in, OutputWriter out) {
		int count = in.readInt();
		long max = in.readLong();
		final int[] array = IOUtils.readIntArray(in, count);
		Comparator<Integer> comparator = new Comparator<Integer>() {
			public int compare(Integer o1, Integer o2) {
				if (array[o1] != array[o2])
					return array[o1] - array[o2];
				return o1 - o2;
			}
		};
		NavigableSet<Integer> start = new TreapSet<Integer>(comparator);
		NavigableSet<Integer> end = new TreapSet<Integer>(comparator);
		long answer = 0;
		long current = 0;
		for (int i = count - 1; i >= 0; i--) {
			current += end.headSet(i, false).size();
			end.add(i);
		}
		int from = 0;
		for (int i = 0; i < count && from < count; i++) {
			if (from == i) {
				end.remove(i);
				current -= start.tailSet(i, false).size() + end.headSet(i, false).size();
			}
			from = Math.max(from, i + 1);
			current += end.headSet(i, false).size() + start.tailSet(i, false).size();
			start.add(i);
			while (current > max && from < count) {
				end.remove(from);
				current -= start.tailSet(from, false).size() + end.headSet(from, false).size();
				from++;
			}
			answer += count - from;
		}
		out.printLine(answer);
	}
}

class InputReader {

	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 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 boolean isSpaceChar(int c) {
		if (filter != null)
			return filter.isSpaceChar(c);
		return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	}

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

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

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

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

	}

class IOUtils {

	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;
	}

	}

class TreapSet<K> implements NavigableSet<K> {
	protected static final Random rnd = new Random(239);

	protected final Node nullNode;
	protected final Comparator<? super K> comparator;
	protected Node root;
	private final K from;
	private final K to;
	private final boolean fromInclusive;
	private final boolean toInclusive;

	public TreapSet() {
		this((Comparator<? super K>)null);
	}

	public TreapSet(Comparator<? super K> comparator) {
		this(null, null, false, false, comparator, null, null);
	}

	public TreapSet(Iterable<? extends K> collection) {
		this(collection, null);
	}

	public TreapSet(Iterable<? extends K> collection, Comparator<? super K> comparator) {
		this(comparator);
		addAll(collection);
	}

	protected TreapSet(K from, K to, boolean fromInclusive, boolean toInclusive, Comparator<? super K> comparator, Node root, Node nullNode) {
		this.comparator = comparator;
		this.from = from;
		this.to = to;
		this.fromInclusive = fromInclusive;
		this.toInclusive = toInclusive;
		if (nullNode == null)
			nullNode = new NullNode();
		if (root == null)
			root = nullNode;
		this.root = root;
		this.nullNode = nullNode;
	}

	public boolean addAll(Iterable<? extends K> collection) {
		boolean result = false;
		for (K element : collection)
			result |= add(element);
		return result;
	}

	public K lower(K k) {
		Node target = root.lower(k);
		if (target == nullNode)
			return null;
		if (belongs(target.key))
			return target.key;
		return null;
	}

	private boolean belongs(K key) {
		int valueFrom = compare(from, key);
		int valueTo = compare(key, to);
		return (valueFrom < 0 || valueFrom == 0 && fromInclusive) && (valueTo < 0 || valueTo == 0 && toInclusive);
	}

	public K floor(K k) {
		Node target = root.floor(k);
		if (target == nullNode)
			return null;
		if (belongs(target.key))
			return target.key;
		return null;
	}

	public K ceiling(K k) {
		Node target = root.ceil(k);
		if (target == nullNode)
			return null;
		if (belongs(target.key))
			return target.key;
		return null;
	}

	public K higher(K k) {
		Node target = root.higher(k);
		if (target == nullNode)
			return null;
		if (belongs(target.key))
			return target.key;
		return null;
	}

	public K pollFirst() {
		K first = first();
		if (first == null)
			throw new NoSuchElementException();
		root.erase(first);
		return first;
	}

	public K pollLast() {
		K last = last();
		if (last == null)
			throw new NoSuchElementException();
		root.erase(last);
		return last;
	}

	public int size() {
		if (from == null && to == null)
			return root.size;
		if (from == null) {
			Node to = toInclusive ? root.floor(this.to) : root.lower(this.to);
			if (to == nullNode)
				return 0;
			return root.indexOf(to) + 1;
		}
		if (to == null) {
			Node from = fromInclusive ? root.ceil(this.from) : root.higher(this.from);
			if (from == nullNode)
				return 0;
			return root.size - root.indexOf(from);
		}
		Node from = fromInclusive ? root.ceil(this.from) : root.higher(this.from);
		if (from == nullNode || !belongs(from.key))
			return 0;
		Node to = toInclusive ? root.floor(this.to) : root.lower(this.to);
		return root.indexOf(to) - root.indexOf(from) + 1;
	}

	public boolean isEmpty() {
		return size() == 0;
	}

	public boolean contains(Object o) {
		return belongs((K) o) && root.search((K) o) != nullNode;
	}

	public Iterator<K> iterator() {
		return new Iterator<K>() {
			private K current = first();

			public boolean hasNext() {
				return current != null;
			}

			public K next() {
				K result = current;
				current = higher(current);
				return result;
			}

			public void remove() {
				TreapSet.this.remove(current);
			}
		};
	}

	public Object[] toArray() {
		Object[] array = new Object[size()];
		int index = 0;
		for (K key : this)
			array[index++] = key;
		return array;
	}

	public <T> T[] toArray(T[] a) {
		if (a.length < size())
			throw new IllegalArgumentException();
		int index = 0;
		for (K key : this)
			a[index++] = (T) key;
		return a;
	}

	public boolean add(K k) {
		if (k == null)
			throw new NullPointerException();
		if (contains(k))
			return false;
		root = root.insert(createNode(k));
		return true;
	}

	protected Node createNode(K k) {
		return new Node(k, rnd.nextLong());
	}

	public boolean remove(Object o) {
		if (!contains(o))
			return false;
		//noinspection unchecked
		root = root.erase((K) o);
		return true;
	}

	public boolean containsAll(Collection<?> c) {
		for (Object o : c) {
			if (!contains(o))
				return false;
		}
		return true;
	}

	public boolean addAll(Collection<? extends K> c) {
		return addAll((Iterable<? extends K>)c);
	}

	public boolean retainAll(Collection<?> c) {
		List<K> toRemove = new ArrayList<K>();
		for (K key : this) {
			if (!c.contains(key))
				toRemove.add(key);
		}
		return removeAll(toRemove);
	}

	public boolean removeAll(Collection<?> c) {
		boolean result = false;
		for (Object o : c)
			result |= remove(o);
		return result;
	}

	public void clear() {
		retainAll(Collections.<Object>emptySet());
	}

	public NavigableSet<K> descendingSet() {
		throw new UnsupportedOperationException();
	}

	public Iterator<K> descendingIterator() {
		return new Iterator<K>() {
			private K current = last();

			public boolean hasNext() {
				return current != null;
			}

			public K next() {
				K result = current;
				current = lower(current);
				return result;
			}

			public void remove() {
				TreapSet.this.remove(current);
			}
		};
	}

	public NavigableSet<K> subSet(K fromElement, boolean fromInclusive, K toElement, boolean toInclusive) {
		return new TreapSet<K>(fromElement, toElement, fromInclusive, toInclusive, comparator, root, nullNode);
	}

	public NavigableSet<K> headSet(K toElement, boolean inclusive) {
		return subSet(null, false, toElement, inclusive);
	}

	public NavigableSet<K> tailSet(K fromElement, boolean inclusive) {
		return subSet(fromElement, inclusive, null, false);
	}

	public Comparator<? super K> comparator() {
		return comparator;
	}

	public SortedSet<K> subSet(K fromElement, K toElement) {
		return subSet(fromElement, true, toElement, false);
	}

	public SortedSet<K> headSet(K toElement) {
		return subSet(null, false, toElement, false);
	}

	public SortedSet<K> tailSet(K fromElement) {
		return tailSet(fromElement, true);
	}

	public K first() {
		if (isEmpty())
			return null;
		if (from == null)
			return root.first().key;
		if (fromInclusive)
			return ceiling(from);
		return higher(from);
	}

	public K last() {
		if (isEmpty())
			return null;
		if (to == null)
			return root.last().key;
		if (toInclusive)
			return floor(to);
		return lower(to);
	}

	protected int compare(K first, K second) {
		if (first == null || second == null)
			return -1;
		if (comparator != null)
			return comparator.compare(first, second);
		//noinspection unchecked
		return ((Comparable<? super K>)first).compareTo(second);
	}

	protected class Node {
		protected final K key;
		protected final long priority;
		protected Node left;
		protected Node right;
		protected int size;

		protected Node(K key, long priority) {
			this.key = key;
			this.priority = priority;
			left = nullNode;
			right = nullNode;
			size = 1;
		}

		protected Object[] split(K key) {
			if (compare(key, this.key) < 0) {
				Object[] result = left.split(key);
				left = (Node) result[1];
				result[1] = this;
				updateSize();
				return result;
			}
			Object[] result = right.split(key);
			right = (Node) result[0];
			result[0] = this;
			updateSize();
			return result;
		}

		protected void updateSize() {
			size = left.size + right.size + 1;
		}

		protected Node insert(Node node) {
			if (node.priority > priority) {
				Object[] result = split(node.key);
				node.left = (Node) result[0];
				node.right = (Node) result[1];
				node.updateSize();
				return node;
			}
			if (compare(node.key, this.key) < 0) {
				left = left.insert(node);
				updateSize();
				return this;
			}
			right = right.insert(node);
			updateSize();
			return this;
		}

		protected Node merge(Node left, Node right) {
			if (left == nullNode)
				return right;
			if (right == nullNode)
				return left;
			if (left.priority > right.priority) {
				left.right = left.right.merge(left.right, right);
				left.updateSize();
				return left;
			}
			right.left = right.left.merge(left, right.left);
			right.updateSize();
			return right;
		}

		protected Node erase(K key) {
			int value = compare(key, this.key);
			if (value == 0)
				return merge(left, right);
			if (value < 0) {
				left = left.erase(key);
				updateSize();
				return this;
			}
			right = right.erase(key);
			updateSize();
			return this;
		}

		protected Node lower(K key) {
			if (compare(key, this.key) <= 0)
				return left.lower(key);
			Node result = right.lower(key);
			if (result == nullNode)
				return this;
			return result;
		}

		protected Node floor(K key) {
			if (compare(key, this.key) < 0)
				return left.floor(key);
			Node result = right.floor(key);
			if (result == nullNode)
				return this;
			return result;
		}

		protected Node higher(K key) {
			if (compare(key, this.key) >= 0)
				return right.higher(key);
			Node result = left.higher(key);
			if (result == nullNode)
				return this;
			return result;
		}

		protected Node ceil(K key) {
			if (compare(key, this.key) > 0)
				return right.ceil(key);
			Node result = left.ceil(key);
			if (result == nullNode)
				return this;
			return result;
		}

		protected Node first() {
			if (left == nullNode)
				return this;
			return left.first();
		}

		protected Node last() {
			if (right == nullNode)
				return this;
			return right.last();
		}

		protected Node search(K key) {
			int value = compare(key, this.key);
			if (value == 0)
				return this;
			if (value < 0)
				return left.search(key);
			return right.search(key);
		}

		public int indexOf(Node node) {
			if (this == node)
				return left.size;
			if (compare(node.key, this.key) > 0)
				return left.size + 1 + right.indexOf(node);
			return left.indexOf(node);
		}

		}

	private class NullNode extends Node {
        private Object[] splitResult = new Object[2];

		private NullNode() {
			super(null, Long.MIN_VALUE);
			left = this;
			right = this;
			size = 0;
		}

		protected Object[] split(K key) {
            splitResult[0] = splitResult[1] = this;
			return splitResult;
		}

		protected Node insert(Node node) {
			return node;
		}

		protected Node erase(K key) {
			return this;
		}

		protected Node lower(K key) {
			return this;
		}

		protected Node floor(K key) {
			return this;
		}

		protected Node higher(K key) {
			return this;
		}

		protected Node ceil(K key) {
			return this;
		}

		protected Node first() {
			throw new NoSuchElementException();
		}

		protected Node last() {
			throw new NoSuchElementException();
		}

		protected void updateSize() {
		}

		protected Node search(K key) {
			return this;
		}


	}
}

