LC-WC T3 AC bi-pointer 22 lines

class Solution {
    using ll = long long;
public:
    long long countGood(vector<int>& nums, int k) {
        int n = nums.size();
        ll ans = 0;
        ll p = 0;
        map<int, int> cnt;
        for (int i = 0, j = 0; i < n; ++i) {
            while(j < n && p < k) {
                p += cnt[nums[j]];
                cnt[nums[j]]++;
                j++;
            }
            // cout << "i: " << i << " j: " << j << " n - j: " << n - j << endl;
            if (p >= k) ans += n - j + 1;
            cnt[nums[i]]--;
            p -= cnt[nums[i]];
        }
        return ans;
    }
};