Two_pointers_step2E

#include <bits/stdc++.h>
typedef long long ll;
typedef unsigned long long ull;
#define vi vector<int>
#define vll vector<ll>
#define tests int t; cin >> t; while(t--)
#define pb push_back
using namespace std;

template <typename T>
istream& operator >> (istream& i, vector<T>& v) {
    for(T& j : v) i >> j;
    return i;
}

template <typename T>
ostream& operator << (ostream& o, const vector<T>& v) {
    for(T j : v) o << j;
    return o;
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);
    int n, k; cin >> n >> k;
    vi v(n); cin >> v;
    int arr[(int)1e5+5] = {0};
    ll i = 0, j = 0, count = 0, prev = 0;
    int elem = 0;
    while(j < n) {
        while(j < n) {
            if(arr[v[j]] == 0) {
                if(elem == k) {
                    break;
                }
                elem++;
            }
            arr[v[j++]]++;
        }
        count += (j-prev)*(j-prev+1)/2+(j-prev)*(prev-i);
        prev = j;
        if(arr[v[i]] == 1) {
            elem--;
        }
        arr[v[i++]]--;
    }
    cout << count;
    return 0;
}