URAL1306-Sequence Median（优先队列）

#include <iostream>
#include <cstdio>
#include <cstring>
#include <vector>
#include <string>
#include <algorithm>
#include <queue>
using namespace std;
priority_queue<int, vector<int>, greater<int> > pq;
int main(){
    int n;
    while(~scanf("%d",&n)){
        int cnt = n/2+1;
        while(!pq.empty()) pq.pop();
        for(int i = 0; i < n; i++){
            int d;
            cin >> d;
            if(pq.size()<cnt){
                pq.push(d);
            }
            else if(pq.top()<d){
                pq.pop();
                pq.push(d);
            }
        }
        double median;
        if(n&1){
            median = pq.top();
        }else{
            int a = pq.top(); pq.pop();
            int b = pq.top();
            median = (a*1.0+b*1.0)/2.0;
        }
        printf("%.1lf\n",median);

    }
    return 0;
}