Today I have done leetcode's October LeetCoding Challenge with cpp.

October LeetCoding Challenge 14

Description

Maximal Score After Applying K Operations

You are given a 0-indexed integer array nums and an integer k. You have a starting score of 0.

In one operation:

1. choose an index i such that 0 <= i < nums.length,
2. increase your score by nums[i], and
3. replace nums[i] with ceil(nums[i] / 3).

Return the maximum possible score you can attain after applying exactly k operations.

The ceiling function ceil(val) is the least integer greater than or equal to val.

Example 1:

Input: nums = [10,10,10,10,10], k = 5
Output: 50
Explanation: Apply the operation to each array element exactly once. The final score is 10 + 10 + 10 + 10 + 10 = 50.

Example 2:

Input: nums = [1,10,3,3,3], k = 3
Output: 17
Explanation: You can do the following operations:
Operation 1: Select i = 1, so nums becomes [1,4,3,3,3]. Your score increases by 10.
Operation 2: Select i = 1, so nums becomes [1,2,3,3,3]. Your score increases by 4.
Operation 3: Select i = 2, so nums becomes [1,1,1,3,3]. Your score increases by 3.
The final score is 10 + 4 + 3 = 17.

Constraints:

• 1 <= nums.length, k <= 105
• 1 <= nums[i] <= 109

Solution

class Solution {
public:
  long long maxKelements(vector<int>& nums, int k) {
    priority_queue<int> pq;
    for(auto n : nums) {
      pq.push(n);
    }
    long long answer = 0;
    while(k--) {
      auto n = pq.top();
      pq.pop();
      answer += n;
      pq.push(ceil(n / 3.0));
    }
    return answer;
  }
};