动态中位数

 

 对顶堆的应用

#include <bits/stdc++.h>
using namespace std;
int main() {
    int t;
    cin >> t;
    while (t--) {
        int n, m;
        cin >> n >> m;
        cout << n << " " << (m + 1) / 2 << endl;
        priority_queue<int, vector<int>, less<int> > down; //down为大根堆
        priority_queue<int, vector<int>, greater<int> > up; //up为小根堆
        int cnt = 0;
        for (int i = 1; i <= m; 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() << " ";
                cnt++;
                if (cnt % 10 == 0) {
                    cout << endl;
                }
            }
        }
        if (cnt % 10) { 
            cout << endl;
        }
    }
    return 0;
}