1817 - Finding the Users Active Minutes.

Medium

You are given the logs for users' actions on LeetCode, and an integer k. The logs are represented by a 2D integer array logs where each <code>logsi = ID_i, time_i</code> indicates that the user with <code>ID_i</code> performed an action at the minute <code>time_i</code>.

Multiple users can perform actions simultaneously, and a single user can perform multiple actions in the same minute.

The user active minutes (UAM) for a given user is defined as the number of unique minutes in which the user performed an action on LeetCode. A minute can only be counted once, even if multiple actions occur during it.

You are to calculate a 1-indexed array answer of size k such that, for each j (1 <= j <= k), answer[j] is the number of users whose UAM equals j.

Return the array answer as described above.

Example 1:

Input: logs = \[\[0,5],1,2,0,2,0,5,1,3], k = 5

Output: 0,2,0,0,0

Explanation:

The user with ID=0 performed actions at minutes 5, 2, and 5 again. Hence, they have a UAM of 2 (minute 5 is only counted once).

The user with ID=1 performed actions at minutes 2 and 3. Hence, they have a UAM of 2.

Since both users have a UAM of 2, answer2 is 2, and the remaining answerj values are 0.

Example 2:

Input: logs = \[\[1,1],2,2,2,3], k = 4

Output: 1,1,0,0

Explanation:

The user with ID=1 performed a single action at minute 1. Hence, they have a UAM of 1.

The user with ID=2 performed actions at minutes 2 and 3. Hence, they have a UAM of 2.

There is one user with a UAM of 1 and one with a UAM of 2.

Hence, answer1 = 1, answer2 = 1, and the remaining values are 0.

Constraints:

• <code>1 <= logs.length <= 10⁴</code>

• <code>0 <= ID_i<= 10⁹</code>

• <code>1 <= time_i<= 10⁵</code>

• k is in the range <code>The maximum **UAM** for a user, 10⁵</code>.