```cpp
0. #include <cstdio>
#include <algorithm>
#include <queue>
using namespace std;
queue<int> q;
int m,n,a[1010],num,x;
int main()
{
scanf("%d%d",&m,&n);
for (int i=1;i<=n;i++)
{
scanf("%d",&x);
if (!a[x])
{
if (q.size()>=m)
{
a[q.front()]=0;
q.pop();
}
num++;
a[x]=1;
q.push(x);
}
}
printf("%d",num);
return 0;
}
```
by wwnf @ 2017-10-11 00:34:51