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

int n, m;
struct Node
{
    int l, r;
    LL mn;
}tr[N * 4];

void pushup(int u)
{
    tr[u].mn = min(tr[u << 1].mn , tr[u << 1 | 1].mn);
}


void build(int u, int l, int r)
{
    if (l == r) tr[u] = {l, r, INF};
    else
    {
        tr[u] = {l, r};
        int mid = l + r >> 1;
        build(u << 1, l, mid), build(u << 1 | 1, mid + 1, r);
        pushup(u);
    }
}

void modify(int u, int l, int r, int d)
{
    if (tr[u].l >= l && tr[u].r <= r)
    {
        tr[u].mn = d;
    }
    else    // 一定要分裂
    {
        int mid = tr[u].l + tr[u].r >> 1;
        if (l <= mid) modify(u << 1, l, r, d);
        if (r > mid) modify(u << 1 | 1, l, r, d);
        pushup(u);
    }
}


 
void solve(){
    int n,k;
    cin>>n>>k;
    vector<int> a(n),f(n+10);
    map<int,vector<int>> mp;
    map<PII,int> id;
    build(1,0,n-1);

    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++) f[i]=-1;

    for(auto [x,y]:mp){
        for(int j=0;j<y.size();j++) id[{x,y[j]}]=j;

        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]);
    }

    LL res=0;



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

        if(id.count({a[i],i})){
            int t=id[{a[i],i}];

            if(t>=k){
                modify(1,a[i],a[i],mp[a[i]][t-k]);
            }
        }

        if(tr[1].mn==INF) res+=f[i]+1;
        else res+=f[i]-tr[1].mn;
    }
    //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;
}