Find median in a stream

Given an input stream of N integers. The task is to insert these numbers into a new stream and find the median of the stream formed by each insertion of X to the new stream.

• Time : O(logn)
• Space : O(n)

class Solution
{
    priority_queue<int> left;
    priority_queue<int, vector<int>, greater<int>> right;
public:
    //Function to insert heap.
    void insertHeap(int &x)
    {
        right.push(x);
        if(right.size() > left.size()) {
            left.push(right.top());
            right.pop();
        }
        
        if(!left.empty() and !right.empty() and left.top() > right.top()) {
            auto l = left.top(); left.pop();
            auto r = right.top(); right.pop();
            left.push(r); right.push(l);
        }
    }

    //Function to return Median.
    double getMedian()
    {
        int sz = left.size() + right.size();
        if(sz == 0) return -1;
        if(sz & 1)
            return left.top();
        return (left.top() + right.top()) / 2.0;
    }
};