class Heap
  attr_reader :size

  def initialize
    @size = 0
    @heap = []
  end

  def empty?
    @size.zero?
  end

  def push(val)
    index = size
    @size += 1

    while index > 0
      parent = (index - 1) / 2

      break if @heap[parent] <= val

      @heap[index] = @heap[parent]
      index = parent
    end

    @heap[index] = val
  end

  alias_method :<<, :push

  def pop
    val = @heap.first
    root = @heap[size - 1]
    @heap[size - 1] = nil
    @size -= 1
    index = 0

    while index * 2 + 1 < @size
      left = 2 * index + 1
      right = left + 1

      if right < size && @heap[right] < @heap[left]
        left = right
      end

      break if @heap[left] >= root

      @heap[index] = @heap[left]
      index = left
    end

    @heap[index] = root
    val
  end

  def top
    @heap.first
  end
end

N, K = gets.split.map(&:to_i)
P = gets.split.map(&:to_i)

list = []

sum = 0
ans = 0

min_heap = Heap.new
max_heap = Heap.new

no_sort = false
gone = Hash.new(false)
cur = -1
suc = 0

N.times do |i|
  if cur < P[i]
    suc += 1
  else
    suc = 1
  end

  cur = P[i]
  
  min_heap.push(P[i])
  max_heap.push(-P[i])

  next if K - 1 > i

  no_change = false

  if i >= K
    v = P[i - K]
    gone[v] = true

    while !max_heap.empty? && gone[-max_heap.top]
      max_heap.pop
    end

    if -max_heap.top == P[i] && min_heap.top == v
      no_change = true
    end

    while !min_heap.empty? && gone[min_heap.top]
      min_heap.pop
    end
  end

  if suc < K
    ans += 1 unless no_change
  else
    no_sort = true
  end
end

if no_sort
  ans += 1
end

puts ans
