3859. Count Subarrays With K Distinct Integers - Solution & Explanation

Problem Statement

You are given an integer array nums and two integers k and m.

Return an integer denoting the count of subarrays of nums such that:

Example 1:

Input: nums = [1,2,1,2,2], k = 2, m = 2

Output: 2

Explanation:

The possible subarrays with k = 2 distinct integers, each appearing at least m = 2 times are:

Subarray	Distinct numbers	Frequency
[1, 2, 1, 2]	{1, 2} → 2	{1: 2, 2: 2}
[1, 2, 1, 2, 2]	{1, 2} → 2	{1: 2, 2: 3}

Thus, the answer is 2.

Example 2:

Input: nums = [3,1,2,4], k = 2, m = 1

Output: 3

Explanation:

The possible subarrays with k = 2 distinct integers, each appearing at least m = 1 times are:

Thus, the answer is 3.

Constraints:

Solutions for this problem are being prepared.