2962-Count-Subarrays-Where-Max-Element-Appears-at-Least-K-Times.cs

public class Solution {
    public long CountSubarrays(int[] nums, int k) {
        int maxElement = nums.Max();
        long ans = 0;
        int start = 0, maxElementsInWindow = 0;

        for (int end = 0; end < nums.Length; end++) {
            if (nums[end] == maxElement) {
                maxElementsInWindow++;
            }
            while (k == maxElementsInWindow) {
                if (nums[start] == maxElement) {
                    maxElementsInWindow--;
                }
                start++;
            }
            ans += start; 
        }

        return ans;
    }
}