POJ 1442 Black Box 優先隊列 求前a[k]個數中第k大的數

維護兩個隊列，

開A

#include <iostream>
#include <algorithm>
#include <cstdio>
#include <cstring>
#include <vector>
#include <set>
#include <map>
#include <stack>
#include <queue>

using namespace std;

int a[31000];

int main()
{
    int m, n;
    scanf("%d %d", &m, &n);
    int i, j;
    for(i = 0;i < m;i++){
        scanf("%d", &a[i]);
    }
    int k;
    priority_queue<int, vector<int>, less<int> >big;
    priority_queue<int, vector<int>, greater<int> >small;
    j = 0;
    int t;
    for(i = 1;i <= n;i++){
        scanf("%d", &k);
        while(j < k){
            small.push(a[j]);
            if(!big.empty()&&small.top() < big.top()){
                t = big.top();
                big.pop();
                big.push(small.top());
                small.pop();
                small.push(t);
            }
            j++;
        }
        printf("%d\n", small.top());
        big.push(small.top());
        small.pop();
    }

    return 0;
}