#include <bits/stdc++.h>

using namespace std;

const int OO = 1e9;
const double EPS = 1e-9;

#define ndl cout << '\n'
#define sz(v) int(v.size())
#define pb push_back
#define mp make_pair
#define fs first
#define sc second
#define present(a, x) (a.find(x) != a.end())
#ifdef LOCAL
#define db(...) ({cout << "> Line " << __LINE__  \
		<< ": "; _db(#__VA_ARGS__, __VA_ARGS__);})
#define RNG() rng()
#else
#define db(...) true
#define RNG() true
#endif

template<class T>
void _db(const char *dbStr, T e) {
	cout << dbStr << " = " << e << endl;
}
template<class T, class... L>
void _db(const char *dbStr, T e, L... r) {
  while(*dbStr != ',') cout << *dbStr++;
  cout << " = " << e << ','; _db(dbStr + 1, r...);
}
template<class S, class T>
ostream& operator<<(ostream& o, const map<S, T>& v) {
	o << "["; int i = 0;
	for (const pair<S, T>& pr : v) o << (!i++ ? "" : ", ") << "{"
	<< pr.fs << " : " << pr.sc << "}"; return o << "]";
}
template<template <class, class...> class S, class T, class... L>
ostream& operator<<(ostream& o, const S<T, L...>& v) {
	o << "["; int i = 0;
	for (const auto& e : v) o << (!i++ ? "" : ", ") << e;
	return o << "]";
}
template<class S, class T>
ostream& operator<<(ostream& o, const pair<S, T>& pr) {
	return o << "(" << pr.fs << ", " << pr.sc << ")";
}
ostream& operator<<(ostream& o, const string& s) {
	for (const char& c : s) o << c;
	return o;
}

template<class T> using V = vector<T>;
template<class T> using VV = V<V<T>>;
template<class T> using VVV = VV<V<T>>;
using ll = long long;
using pii = pair<int, int>;
using vi = V<int>;
using vii = V<pii>;
using vvi = VV<int>;
using mii = map<int, int>;
using umii = unordered_map<int, int>;
using si = set<int>;
using usi = unordered_set<int>;

int N, K, ans;
vi P, sorted;
V<bool> bad, vis;
vvi adj;

void dfs(int u) {
	vis[u] = true;
	for (auto& v : adj[u]) {
		if (!vis[v])
			dfs(v);
	}
}

int main() {
	#ifdef LOCAL
	auto stTime = clock();
//	freopen("in.txt", "r", stdin);
	mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
	#endif
	ios::sync_with_stdio(false);
	cout.precision(10);
	cin.tie(0);

	cin >> N >> K;
	P.assign(N + 1, 0);
	bad.assign(N + 1, 0);
	vis.assign(N + 1, 0);
	adj.assign(N + 1, vi());

	for (int i = 1; i <= N; ++i) {
		cin >> P[i];
	}
	for (int i = 1; i <= N - 1; ++i) {
		if (P[i] > P[i + 1])
			bad[i] = true;
	}

	{
		int sum = 0;
		for (int i = 1; i <= K - 1; ++i) {
			sum += bad[i];
		}

		for (int i = 1; i <= N - K + 1; ++i) {
			if (!sum)
				sorted.pb(i);
			sum += bad[i + K - 1];
			sum -= bad[i];
		}

		db(sorted);

		for (int i = 1; i < sz(sorted); ++i) {
			int u = sorted[i], v = sorted[i - 1];
			adj[u].pb(v);
			adj[v].pb(u);
		}

	}

	db(adj);

	{

		set<int> s;

		for (int i = 2; i <= K; ++i) {
			s.insert(P[i]);
		}

		for (int i = 1; i <= N - K; ++i) {
			if (P[i] < *s.begin() && P[i + K] > *s.rbegin())
				adj[i].pb(i + 1), adj[i + 1].pb(i);
			s.insert(P[i + K]);
			s.erase(P[i + 1]);
		}
	}

	db(adj);

	for (int i = 1; i <= N - K + 1; ++i) {
		if (!vis[i])
			dfs(i), ++ans;
	}

	cout << ans << '\n';

	#ifdef LOCAL
	cout << "\n\n\nExecution time: " <<
		(clock() - stTime) * 1e3 / CLOCKS_PER_SEC << " ms" << endl;
	#endif
    return 0;
}


Measured memory_bytes: 19064