方法如下：
1. 开两个优先队列，一个大根堆一个小根堆
```cpp
priority_queue<int, vector<int>, less<int> > a;
//大根
priority_queue<int, vector<int>, greater<int> > s;
//小根
```
2. 把输入的前$m$个数塞进大根堆
```cpp
for (register int i = 1; i <= m; ++i)
{
int num;
scanf("%d", &num); //优先队列不能直接输入堆顶
a.push(num); //只能用中间变量输入
//然后再进堆
}
```
3. 对接下来的$n-m$个数进行筛选，**如果比大根堆的根小，就去除根，并把这个数塞进去**
```cpp
for (register int i = m + 1, num; i <= n; ++i)
{
scanf("%d", &num);
if (num < a.top()) a.pop(), a.push(num);
}
```
4. 把大根堆里的数倒进小根堆里
```cpp
for (register int i = 1; i <= m; ++i)
{
s.push(a.top()); //大根堆堆顶倒入小根堆
a.pop(); //大根堆堆顶出堆
}
```
5. 输出即可。
完整代码如下：
```cpp
#include <stdio.h>
#include <queue>
#include <algorithm>
using namespace std;
priority_queue<int, vector<int>, less<int> > a;
priority_queue<int, vector<int>, greater<int> > s;
int maxn;
int main()
{
int n, m, miss = 0;
scanf("%d %d", &n, &m);
for (register int i = 1; i <= m; ++i)
{
int num;
scanf("%d", &num);
a.push(num);
}
for (register int i = m + 1, num; i <= n; ++i)
{
scanf("%d", &num);
if (num < a.top())
{
a.pop();
a.push(num);
}
}
for (register int i = 1; i <= m; ++i)
{
s.push(a.top());
a.pop();
}
while(s.size()) printf("%d\n", s.top()), s.pop();
}
```
求过求顶，让更多的人看到。
拒绝抄袭。