$\huge \color{orange}{成魔之路->}$ $\huge \color{purple}{算法提高课题解}$

思路：

1. 建立大根堆 down 和小根堆 up
2. 小根堆 up 里面的所有元素都必须大于大根堆 down 里面的所有元素
3. 元素个数：down.size() == up.size() || down.size() == up.size + 1

完整代码

#include<bits/stdc++.h>

using namespace std;

int main()
{
    int T;
    cin>>T;

    while(T--)
    {
        int m,n;
        cin>>m>>n;
        cout<<m<<' '<<(n+1)/2<<endl;

        priority_queue<int> down;
        priority_queue<int,vector<int>,greater<int>> up;

        int cnt=0;
        for(int i=1;i<=n;i++)
        {
            int x;
            cin>>x;

            if(down.empty()||x<=down.top()) down.push(x);
            else up.push(x);

            if(down.size()>up.size()+1) up.push(down.top()),down.pop();
            if(up.size()>down.size()) down.push(up.top()),up.pop();

            if(i%2)
            {
                cout<<down.top()<<' ';
                if(++cnt%10==0) puts("");
            }
        }

        if(cnt%10) puts("");
    }

    return 0;
}