#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef pair<ll,ll> P;
 
long long int INF = 3e18;
double Pi = 3.1415926535897932384626;
 
vector<ll> G[550010];
//vector<P> tree[500010];
priority_queue <ll> pql;
priority_queue <P> pqp;
//big priority queue
priority_queue <ll,vector<ll>,greater<ll> > pqls;
priority_queue <P,vector<P>,greater<P> > pqps;
//small priority queue
//top pop
 
int dx[8]={1,0,-1,0,1,1,-1,-1};
int dy[8]={0,1,0,-1,1,-1,-1,1};
char dir[] = "DRUL";
//ll bit[500005];
//↓,→,↑,←
 
 
#define p(x) cout<<x<<"\n";
#define el cout<<endl;
#define pe(x) cout<<(x)<<" ";
#define ps(x) cout<<fixed<<setprecision(25)<<x<<endl;
#define pu(x) cout<<(x);
#define pb push_back
#define lb lower_bound
#define ub upper_bound
#define CLEAR(a) a = decltype(a)(); 
 
 
ll mod = 998244353;

ll rui(ll number1,ll number2){

    if(number2 == 0){
        return 1;
    }else{
        ll number3 = rui(number1,number2 / 2);
        number3 *= number3;
        number3 %= mod;
        if(number2%2==1){
            number3 *= number1;
            number3 %= mod;
        }
        return number3;
    }
}
ll gcd(ll number1,ll number2){
 
    if(number1 > number2){
        swap(number1,number2);
    }
    if(number1 == 0 || number1 == number2){
        return number2;
    }else{
        return gcd(number2 % number1,number1);
    }
}
void YES(bool condition){
 
    if(condition){
        p("YES");
    }else{
        p("NO");
    }
    return;
}
void Yes(bool condition){
 
    if(condition){
        p("Yes");
    }else{
        p("No");
    }
    return;
}

/*
ll fact[800005],rfact[800005];

void c3_init(){
    fact[0] = rfact[0] = 1;
    for(ll i=1; i<=800000; i++){
        fact[i] = (fact[i-1]*i) % mod;
    }
    rfact[800000] = rui(fact[800000],mod - 2);
    for(ll i=800000; i>=1; i--){
       rfact[i-1] = rfact[i] * i;
       rfact[i-1] %= mod;
    }
    return;}
ll c3(ll n,ll r){
    return (((fact[n] * rfact[r]) % mod ) * rfact[n-r]) % mod;}
*/
 
ll n,m,num,sum,a,b,c,d,e,g,h,w,i,j,q,r,l;
ll k,ans;
ll x[500005],y[500005],z[500005];
ll small[500005],large[500005];

ll deq[500005];
char s[500005];

int main(){
    cin >> n >> k;
    for(int i=0;i<n;i++){
        cin >> x[i];
        x[i]++;
    }
    for(int i=0;i<n-1;i++){
        if(x[i] < x[i+1]){
            y[i+1]++;
        }
    }
    for(int i=0;i<n+2;i++){
        y[i+1] += y[i];
        //pe(y[i+1]);
    }
    //el;
    ll s = 0, t = 0;
    for(int i=0;i<n;i++){
        while(s < t && x[deq[t-1]] >= x[i])t--;
        deq[t++] = i;

        if(i - k + 1 >= 0){
            small[i - k + 1] = x[deq[s]];
            if(deq[s] == i - k + 1){
                s++;
            }
        }
    }
    for(int i=0;i<=n-k;i++){
       // pe(small[i]);
    }
    //el;
    for(int i=0;i<n;i++){
        x[i] *= -1;
    }
    s = 0, t = 0;
    for(int i=0;i<n;i++){
        while(s < t && x[deq[t-1]] >= x[i])t--;
        deq[t++] = i;

        if(i - k + 1 >= 0){
            large[i - k + 1] = -1 * x[deq[s]];
            if(deq[s] == i - k + 1){
                s++;
            }
        }
    }
    for(int i=0;i<=n-k;i++){
        //pe(large[i]);
    }
    //el;
    for(int i=0;i<n;i++){
        x[i] *= -1;
    }
    ans = 1;
    if(y[k-1] - y[0] >= k - 1){
        a++;
    }
    for(int i=0;i<n-k;i++){
        //p("ya");
        if(y[k+i] - y[i+1] == k - 1){
            //p("kitazo");
            if(a == 1){
                continue;
            }else{
                a++;
                ans++;
            }
        }else if(small[i] == x[i] && large[i+1] == x[i+k]){
            continue;
        }else{
            ans++;
        }
    }

    p(ans);
    

    return 0;

}


















Measured memory_bytes: 30464