#include "bits/stdc++.h"
using namespace std;
using ll = long long;

const ll N = 1e6 + 1;
const ll M = 1e9 + 7;

struct STN {ll val, cnt, lazy;};
struct SegmentTree {
    const STN DEF = {0, 1, 0};
    const STN DED = {10, 0, 0};
    vector<STN> s; ll uu, vv;
    SegmentTree(ll n): s(4 * n + 10, DEF), uu(1), vv(n) {}
    
    STN merge(STN a, STN b) {
        if (a.cnt == 0) return b;
        if (b.cnt == 0) return a;
        
        STN res;
        if (a.val == b.val) res.cnt = a.cnt + b.cnt;
        else if (a.val < b.val) res.cnt = a.cnt;
        else res.cnt = b.cnt;

        res.val = min(a.val, b.val);
        res.lazy = 0;
        return res;
    }
    void down(ll id, ll l, ll r) {
        if (s[id].lazy == 0) return;
        ll tmp = s[id].lazy;
        s[id].lazy = 0;

        s[id << 1].val += tmp;
        s[id << 1 | 1].val += tmp;
        s[id << 1].lazy += tmp;
        s[id << 1 | 1].lazy += tmp;
    }
    void update(ll u, ll v, ll val) {update(u, v, val, 1, uu, vv);}
    void update(ll u, ll v, ll val, ll id, ll l, ll r) {
        if (l > v || r < u) return;
        if (u <= l && r <= v) {
            s[id].val += val;
            s[id].lazy += val;
            return;
        }
        down(id, l, r);
        ll mid = (l + r) >> 1;
        update(u, v, val, id << 1, l, mid);
        update(u, v, val, id << 1 | 1, mid + 1, r);
        s[id] = merge(s[id << 1], s[id << 1 | 1]);
    }
    STN get(ll u, ll v) {return get(u, v, 1, uu, vv);}
    STN get(ll u, ll v, ll id, ll l, ll r) {
        if (l > v || r < u) return DED;
        if (u <= l && r <= v) return s[id];
        down(id, l, r);
        ll mid = (l + r) >> 1;
        return merge(get(u, v, id << 1, l, mid), get(u, v, id << 1 | 1, mid + 1, r));
    }
};

ll n, k;
ll a[N];
vector<ll> v[N];

void doTest(ll testID) {
    cin >> n >> k; SegmentTree st(n);
    for (int i = 1; i <= n; i ++) cin >> a[i], st.update(i, i, 0);
    for (int i = 1; i <= n; i ++) v[i].push_back(0);
    for (int i = 1; i <= n; i ++) v[a[i]].push_back(i);

    ll res = 0;
    for (int i = 1; i <= n; i ++) {
        ll pos = lower_bound(v[a[i]].begin(), v[a[i]].end(), i) - v[a[i]].begin();
        if (pos - k - 1 >= 0) {
            ll l = v[a[i]][pos - k - 1] + 1, r = v[a[i]][pos - k];
            st.update(l, r, -1);
        }
        if (pos - k >= 0) {
            ll l = v[a[i]][pos - k] + 1, r = v[a[i]][pos - k + 1];
            st.update(l, r, 1);
        }
        STN node = st.get(1, i);
        if (node.val == 0) res += node.cnt;
        // cout << "Debug: " << i << ' ' << pos << ' ' << node.val << ' ' << node.cnt << endl;
        // for (int i = 1; i <= n; i ++) cout << st.get(i, i).val << ' '; cout << endl;
    }
    cout << res;
}

signed main() {
    ios_base::sync_with_stdio(0); cin.tie(0);

    int test = 1; 
    // cin >> test;
    for (int _ = 1; _ <= test; _ ++) doTest(test);
}