数据流中的中位数

template<typename T> class DynamicArray
{
public:
    void Insert(T num)
    {
        if(((min.size() + max.size()) & 1) == 0)
        {
            if(max.size() > 0 && num < max[0])
            {
                max.push_back(num);
                push_heap(max.begin(), max.end(), less<T>());

                num = max[0];

                pop_heap(max.begin(), max.end(), less<T>());
                max.pop_back();
            }

            min.push_back(num);
            push_heap(min.begin(), min.end(), greater<T>());
        }
        else
        {
            if(min.size() > 0 && min[0] < num)
            {
                min.push_back(num);
                push_heap(min.begin(), min.end(), greater<T>());

                num = min[0];

                pop_heap(min.begin(), min.end(), greater<T>());
                min.pop_back();
            }

            max.push_back(num);
            push_heap(max.begin(), max.end(), less<T>());
        }
    }

    T GetMedian()
    {
        int size = min.size() + max.size();
        if(size == 0)
            throw exception("No numbers are available");

        T median = 0;
        if((size & 1) == 1)
            median = min[0];
        else
            median = (min[0] + max[0]) / 2;

        return median;
    }

private:
    vector<T> min;
    vector<T> max;
};