Max Number of K-Sum Pairs LeetCode solution in C++

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class Solution {
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 public:
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  int maxOperations(vector<int> &nums, int k) {
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    unordered_map<int, int> Map;
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    for (auto &num : nums) Map[num]++; // count freq of nums
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    int ans = 0;
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    for (auto it = Map.begin(); it != Map.end(); ++it) {
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      int num = it->first, count = it->second;
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      if (k - num == num)
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        ans += count / 2;            // if num is half of k add half of it's count in ans
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      else if (Map.count(k - num)) { // find k-num in nums and add min freq of
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                                     // num or k-num to ans
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        int Min = min(count, Map[k - num]);
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        ans += Min;
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        Map[num] -= Min;
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        Map[k - num] -= Min;
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      }
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    }
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    return ans;
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  }
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};