HDU 4006 The kth great number 【优先队列求第K大数】

The kth great number

Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 65768/65768 K (Java/Others)

Total Submission(s): 7004 Accepted Submission(s): 2857



Problem Description
Xiao Ming and Xiao Bao are playing a simple Numbers game. In a round Xiao Ming can choose to write down a number, or ask Xiao Bao what the kth great number is. Because the number written by Xiao Ming is too much, Xiao Bao is feeling
giddy. Now, try to help Xiao Bao.


Input
There are several test cases. For each test case, the first line of input contains two positive integer n, k. Then n lines follow. If Xiao Ming choose to write down a number, there will be an " I" followed by a number that Xiao Ming
will write down. If Xiao Ming choose to ask Xiao Bao, there will be a "Q", then you need to output the kth great number.



Output
The output consists of one integer representing the largest number of islands that all lie on one line.



Sample Input

8 3
I 1
I 2
I 3
Q
I 5
Q
I 4
Q

Sample Output

1
2
3

/*题解：

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

greater算子，由小到大出队列

less算子，由大到小出队列

*/

#include<cstdio>
#include<queue>
#include<vector>
using namespace std;
priority_queue<int,vector<int>,greater<int> >q;
int main()
{
    int n,k,x;
    char c;
    while(scanf("%d %d",&n,&k)!=EOF)
    {
        while(!q.empty()) q.pop();
        while(n--)
        {
            getchar();
            scanf("%c",&c);
            if(c=='I')
            {
                scanf("%d",&x);
                q.push(x);
            }
            while(q.size()>k) q.pop();
            if(c=='Q')
            {
                printf("%d\n",q.top());
            }
        }
    }
    return 0;
}