P1801 黑匣子

合集 - 数据结构(28)

1.P3957 [NOIP2017 普及组] 跳房子2024-03-062.P2034 选择数字2024-03-093.P1714 切蛋糕2024-03-094.E - Insert or Erase2024-03-105.P4147 玉蟾宫2024-03-106.P2866 [USACO06NOV] Bad Hair Day S2024-03-107.P2032 扫描2024-03-108.P1884 [USACO12FEB] Overplanting S2024-03-109.P5905 【模板】全源最短路（Johnson）2024-03-11

10.P1801 黑匣子2024-03-29

11.P2168 [NOI2015] 荷马史诗2024-03-3012.P8306 【模板】字典树2024-03-3013.P1481 魔族密码2024-03-3014.P4341 [BJWC2010] 外星联络2024-04-0115.P1470 [USACO2.3] 最长前缀 Longest Prefix2024-04-0116.P3384 【模板】重链剖分/树链剖分2024-04-0317.P10288 [GESP样题 八级] 区间2024-04-1618.P2161 [SHOI2009] 会场预约2024-04-1719.P1878 舞蹈课2024-05-1720.P9691 [GDCPC2023] Base Station Construction2024-05-1821.P3611 [USACO17JAN] Cow Dance Show S2024-05-2022.F. Cutting Game2024-05-2123.G. Money Buys Less Happiness Now2024-05-2224.D. In Love2024-06-2925.F. Selling a Menagerie2024-06-2926.D. Learning to Paint2024-07-1927.P4588 [TJOI2018] 数学计算2024-07-2028.P3522 [POI2011] TEM-Temperature2024-07-21

收起

原题链接

题解

用由于本题具有线性特征（总是不减？）所以可以用两个堆来维护第i小的元素，

code

#include<bits/stdc++.h>
using namespace std;
int a[200005];
int main()
{
    ios::sync_with_stdio(false);
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;i++) cin>>a[i];

    int sizes=0,it=1;
    priority_queue<int,vector<int> ,greater<int> > qsmall;
    priority_queue<int> qbig;
    for(int i=1;i<=m;i++)
    {
        int x;
        cin>>x;
        while(it<=x)
        {
            if(qbig.size()<i-1)qbig.push(a[it]);//放入决策
            else qsmall.push(a[it]);

            while(qsmall.size()&&qbig.size()&&qbig.top()>qsmall.top())//维护平衡
            {
                int d1=qbig.top(),d2=qsmall.top();
                qbig.pop();
                qsmall.pop();
                qbig.push(d2);
                qsmall.push(d1);
            }
            it++;
        }

        while((qbig.size()<i-1))//维护大小
        {
            qbig.push(qsmall.top());
            qsmall.pop();
        }
        //printf("size:%d,%d\n",qsmall.size(),qbig.size());
        cout<<qsmall.top()<<endl;
    }
    return 0;
}