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

June LeetCoding Challenge 28

Description

Find Subsequence of Length K With the Largest Sum

You are given an integer array nums and an integer k. You want to find a subsequence of nums of length k that has the largest sum.

Return any such subsequence as an integer array of length k.

A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.

Example 1:

Input: nums = [2,1,3,3], k = 2
Output: [3,3]
Explanation:
The subsequence has the largest sum of 3 + 3 = 6.

Example 2:

Input: nums = [-1,-2,3,4], k = 3
Output: [-1,3,4]
Explanation: 
The subsequence has the largest sum of -1 + 3 + 4 = 6.

Example 3:

Input: nums = [3,4,3,3], k = 2
Output: [3,4]
Explanation:
The subsequence has the largest sum of 3 + 4 = 7. 
Another possible subsequence is [4, 3].

Constraints:

• 1 <= nums.length <= 1000
• -105 <= nums[i] <= 105
• 1 <= k <= nums.length

Solution

class Solution {
public:
  vector<int> maxSubsequence(vector<int>& nums, int k) {
    vector<int> tmp(nums);
    sort(tmp.begin(), tmp.end());
    int len = nums.size();
    multiset<int> candidates;
    for(int i = 1; i <= k; ++i) {
      candidates.insert(tmp[len - i]);
    }
    vector<int> answer;
    for(auto n : nums) {
      if(!candidates.count(n)) continue;
      answer.push_back(n);
      candidates.erase(candidates.find(n));
    }
    return answer;
  }
};

// Accepted
// 49/49 cases passed (11 ms)
// Your runtime beats 7.68 % of cpp submissions
// Your memory usage beats 11.81 % of cpp submissions (14.4 MB)