XDOJ_1004_优先队列

http://acm.xidian.edu.cn/problem.php?id=1042

每次取最小的那两个就好了,维护一个升序的优先队列。

注意小数精度问题。

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<queue>
using namespace std;

priority_queue<double,vector<double>,greater<double> > q;
int n;

int main()
{
    int T;
    scanf("%d",&T);
    while(T--)
    {
        scanf("%d",&n);
        for(int i = 1;i <= n;i++)
        {
            double temp;
            scanf("%lf",&temp);
            q.push(temp);
        }
        for(int i = 1;i < n;i++)
        {
            double a = q.top();
            q.pop();
            double b = q.top();
            q.pop();
            q.push((a+b)/2);
        }
        printf("%.2f\n",q.top()+0.00001);
        q.pop();
    }
    return 0;
}
时间: 2024-10-14 01:40:41

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