#include<bits/stdc++.h>
using namespace std;
typedef  long long LL;
typedef pair<int,int> PII;
const int N=2e5+10,M=1e6+10;
const int mod=1e9+7;
int INF = 1e9;

 
void solve(){
    int n,k;
    cin>>n>>k;
    vector<int> a(n),f(n+10),d(n+10);
    map<int,vector<int>> mp;

    for(int i=0;i<n;i++) cin>>a[i];

    for(int i=0;i<n;i++){
        mp[a[i]].push_back(i);
    }
    for(int i=0;i<n;i++) d[i]=f[i]=-1;
    for(auto [x,y]:mp){
        if(y.size()<k) continue;

        for(int j=k-1;j<y.size();j++) f[y[j]]=max(f[y[j]],y[j-k+1]);
        for(int j=k;j<y.size();j++) d[y[j]]=max(d[y[j]],y[j-k]);
    }

    LL res=0;



    for(int i=0;i<n;i++){
        if(i) f[i]=max(f[i],f[i-1]),d[i]=min(d[i],d[i-1]);

        //cout<<f[i]<<endl;
        //cout<<d[i]<<" ";

        if(d[i]>=f[i]) continue;
        res+=f[i]-d[i];
    }
    //cout<<endl;

    res=(LL)n*(n+1)/2-res;

    cout<<res<<endl;

}
 
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int T=1;
    //cin>>T;
    while(T--) solve();
 
    return 0;
}