Shared code

#include<bits/stdc++.h>
using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define debug()
#define db(x)
#endif


#define INF 1e18
#define eps 1e-6
#define endl '\n'
#define ff first
#define ss second
#define ll long long
#define pb push_back
#define int long long
#define mod 1000000007
#define PI  2 * acos(0.0)
#define pii  pair<int,int>
#define double long double
#define ull unsigned long long
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define rall(a) (a).rbegin(),(a).rend()
#define deci(x) cout << fixed << setprecision(x);
#define rmv(x,a) x.erase(remove(x.begin(),x.end(),a),x.end())
#define unq(x) {x.erase(unique(x.begin(),x.end()),x.end());}
#define shera() ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL)


int32_t main() {
    shera();
    debug();

    int n; cin >> n;
    int k; cin >> k;
    vector<int>v(n + 1);
    map<int, int>mp;
    for (int i = 1; i <= n; i++) {
        cin >> v[i];
    }

    int i = 1, j = 1, cnt = 0, ans = 0;
    for (; i <= n ; i++) {
        if (!mp[v[i]])cnt++;
        if (cnt > k) {
            while (1) {
                mp[v[j]]--;
                if (!mp[v[j]]) {
                    cnt--;
                    j++;
                    break;
                }
                j++;
            }
        }
        mp[v[i]]++;
        ans += (i - j + 1);
    }

    cout << ans  << endl;


    return 0;
}


/*
5 2
1 2 3 1 1

j=1, i=1
(i - j + 1) = 1 -> {1}

j=1, i=2
(i - j + 1) = 2 -> {1,2},{2}

j=2, i=3
(i - j + 1) = 2 -> {2,3},{3}

j=3, i=4
(i - j + 1) = 2 -> {3,1},{1}

j=3, i=5
(i - j + 1) = 3 -> {3,1,1},{1,1},{1}

*/