2195 - Append K Integers With Minimal Sum\.

Medium

You are given an integer array nums and an integer k. Append k unique positive integers that do not appear in nums to nums such that the resulting total sum is minimum.

Return the sum of the k integers appended to nums.

Example 1:

Input: nums = 1,4,25,10,25, k = 2

Output: 5

Explanation: The two unique positive integers that do not appear in nums which we append are 2 and 3.

The resulting sum of nums is 1 + 4 + 25 + 10 + 25 + 2 + 3 = 70, which is the minimum.

The sum of the two integers appended is 2 + 3 = 5, so we return 5.

Example 2:

Input: nums = 5,6, k = 6

Output: 25

Explanation: The six unique positive integers that do not appear in nums which we append are 1, 2, 3, 4, 7, and 8.

The resulting sum of nums is 5 + 6 + 1 + 2 + 3 + 4 + 7 + 8 = 36, which is the minimum.

The sum of the six integers appended is 1 + 2 + 3 + 4 + 7 + 8 = 25, so we return 25.

Constraints:

• <code>1 <= nums.length <= 10⁵</code>

• <code>1 <= numsi<= 10⁹</code>

• <code>1 <= k <= 10⁸</code>