Amazon OA SDE Intern | India | Coding | Set - 137

Question

Answer 1

int countUniqueAverages(std::vector<int>& arr) {
    const int n = arr.size();
    if (n <  2) return  0;

    std::sort(arr.begin(), arr.end());
    
    std::unordered_set<double> uniqueAverages;
    
    for (int i =  0; i < n/2; ++i) {
        int lowest = arr[i];
        int highest = arr[n-i-1];
        uniqueAverages.insert((lowest+highest)/2.0);
    }
    
    return uniqueAverages.size();
}