using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace AtCorder
{
	public class Program
	{
		static void Main(string[] args)
		{
			Scanner cin = new Scanner();
			int n = cin.Int();
			int k = cin.Int();
			int[] p = cin.ArrayInt(n);

			var ss = new MultiSet<int>(n);
			for (int i = 0; i < k; i++) {
				ss.Add(p[i]);
			}

			int ren = 0;
			int pp = -1;
			var ni = new bool[n];
			for (int i = 0; i < n; i++) {
				if (p[i] >= pp) {
					ren++;
					if (ren >= k) {
						ni[i] = true;
					}
				} else {
					ren = 1;
				}

				pp = p[i];
			}

			int ans = 1;
			bool isNoSort = ni[k - 1];
			for (int i = k; i < n; i++) {
				int min = ss.Min;
				ss.Remove(p[i - k]);
				ss.Add(p[i]);
				int max = ss.Max;
				if (p[i - k] != min || p[i] != max) {
					if (ni[i]) {
						if (isNoSort == false) {
							++ans;
						}

						isNoSort = true;
					} else {
						++ans;
					}
				}
			}

			Console.WriteLine(ans);
		}
	}

	public class MultiSet<T> :
		IEnumerable<T>,
		System.Collections.IEnumerable,
		ICollection<T>,
		System.Collections.ICollection,
		IReadOnlyCollection<T>
	{
		private readonly SortedSet<T> set_;
		private readonly Dictionary<T, int> counts_ = new Dictionary<T, int>();

		public MultiSet(
			int capacity,
			IEnumerable<T> collection = null,
			IComparer<T> comparer = null)
		{
			counts_ = new Dictionary<T, int>(capacity);
			if (collection == null && comparer == null) {
				set_ = new SortedSet<T>();
			} else if (collection == null) {
				set_ = new SortedSet<T>(comparer);
			} else if (comparer == null) {
				set_ = new SortedSet<T>(collection);
			} else {
				set_ = new SortedSet<T>(collection, comparer);
			}
		}

		public IComparer<T> Comparer => set_.Comparer;
		public int Count { get; private set; }
		public T Max => set_.Max;
		public T Min => set_.Min;

		public bool IsReadOnly => false;

		object System.Collections.ICollection.SyncRoot
			=> (set_ as System.Collections.ICollection).SyncRoot;

		bool System.Collections.ICollection.IsSynchronized
			=> (set_ as System.Collections.ICollection).IsSynchronized;

		public bool Add(T item)
		{
			if (counts_.ContainsKey(item) == false) {
				counts_[item] = 1;
			} else {
				counts_[item]++;
			}

			set_.Add(item);
			++Count;
			return true;
		}

		public bool Remove(T item)
		{
			if (counts_.ContainsKey(item) == false) {
				return false;
			}

			counts_[item]--;
			Count--;
			if (counts_[item] == 0) {
				counts_.Remove(item);
				set_.Remove(item);
			}

			return true;
		}

		public void Clear()
		{
			counts_.Clear();
			Count = 0;
			set_.Clear();
		}

		public bool Contains(T item) => set_.Contains(item);

		public IEnumerator<T> GetEnumerator()
		{
			foreach (var s in set_) {
				for (int i = 0; i < counts_[s]; i++) {
					yield return s;
				}
			}
		}

		System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
			=> GetEnumerator();

		void ICollection<T>.Add(T item) => Add(item);

		public void CopyTo(T[] array, int arrayIndex)
		{
			int index = arrayIndex;
			foreach (var s in set_) {
				for (int i = 0; i < counts_[s]; i++) {
					array[index] = s;
					++index;
				}
			}
		}

		void System.Collections.ICollection.CopyTo(Array array, int index)
		{
		}
	}

	public class Scanner
	{
		private readonly char[] delimiter_ = new char[] { ' ' };
		private string[] buf_;
		private int index_;

		public Scanner()
		{
			buf_ = new string[0];
			index_ = 0;
		}

		public string Next()
		{
			if (index_ < buf_.Length) {
				return buf_[index_++];
			}

			string st = Console.ReadLine();
			while (st == "") {
				st = Console.ReadLine();
			}

			buf_ = st.Split(delimiter_, StringSplitOptions.RemoveEmptyEntries);
			if (buf_.Length == 0) {
				return Next();
			}

			index_ = 0;
			return buf_[index_++];
		}

		public int Int()
		{
			return int.Parse(Next());
		}
		public int[] ArrayInt(int N, int add = 0)
		{
			int[] Array = new int[N];
			for (int i = 0; i < N; i++) {
				Array[i] = Int() + add;
			}
			return Array;
		}

		public long Long()
		{
			return long.Parse(Next());
		}

		public long[] ArrayLong(int N, long add = 0)
		{
			long[] Array = new long[N];
			for (int i = 0; i < N; i++) {
				Array[i] = Long() + add;
			}
			return Array;
		}

		public double Double()
		{
			return double.Parse(Next());
		}

		public double[] ArrayDouble(int N, double add = 0)
		{
			double[] Array = new double[N];
			for (int i = 0; i < N; i++) {
				Array[i] = Double() + add;
			}
			return Array;
		}
	}
}

Measured memory_bytes: 41608