#include<bits/stdc++.h>
#define lch (w<<1)
#define rch ((w<<1)|1)
using namespace std;

const int N = 1e6+5;
const int INF = N;
int n, k;
int a[N],c[N];
vector<int> b[N];
struct rec{
    int val, cnt;
    int resi;
}tr[N<<2];
long long ans;

inline rec mymin(rec a, rec b) {
    if (a.val != b.val) {
        return (a.val < b.val)?a:b;
    }
    return (rec){a.val,a.cnt+b.cnt};
}

void pushdown(int w, int l, int r){
    tr[lch].resi += tr[w].resi;
    tr[lch].val += tr[w].resi;
    tr[rch].resi += tr[w].resi;
    tr[rch].val += tr[w].resi;
    tr[w].resi = 0;
    return ;
}

void add(int w, int l, int r, int L, int R, int y) {
    if (L <= l && r <= R) {
        tr[w].val += y;
        tr[w].resi += y;
        return ;
    }
    if (tr[w].resi) pushdown(w,l,r);
    int mid = (l+r)>>1;
    if (L > R) return;
    if (L <= mid) add(lch,l,mid,L,R,y);
    if (mid < R) add(rch,mid+1,r,L,R,y);
    tr[w] = mymin(tr[lch], tr[rch]);
    return ;
}

rec query(int w,int l, int r, int L, int R) {
    if (L <= l && r <= R) {
        return tr[w];
    }
    if (tr[w].resi) pushdown(w,l,r);
    int mid = (l+r)>>1;
    rec t1 = (rec){INF,0}, t2 = (rec){INF,0};
    if (L>R) return t1;
    if (L <= mid) t1 = query(lch,l,mid,L,R);
    if (mid < R) t2 = query(rch,mid+1,r,L,R);
    return mymin(t1,t2);
}

void build(int w, int l, int r){
    int mid = (l+r)>>1;
    tr[w] = (rec){0,r-l+1};
    if (l>=r) return;
    build(lch,l,mid);
    build(rch,mid+1,r);
    return;
}

int main(){
    ios::sync_with_stdio(false); cin.tie(0);

    cin >> n >> k;
    for (int i = 1;i <= n;++ i) {
        cin >> a[i];
        b[a[i]].push_back(i);
    }
    build(1,1,n);
    for (int r = 1;r <= n;++ r){
        int m = (c[a[r]]++);
        if (m >= k - 1) {
           vector<int> &tmp = b[a[r]];
           if (m == k-1) {
              add(1,1,n,1,tmp[0],+1);
           }
           else {
             add(1,1,n,tmp[m-k]+1,tmp[m-k+1],+1);
             if (m > k) add(1,1,n,tmp[m-k-1]+1,tmp[m-k],-1);
           }
        }
        rec x = query(1,1,n,1,r);
        if (x.val == 0) {
            ans = ans + x.cnt;
        }
    }
    cout << ans << endl;
    return 0;
}