#include <iostream>
#include <cstdio>
#include <queue>
using namespace std;
int n,m,sum=0,head=1,tail=0,a[2010];
int e;
int main()
{
	cin>>m>>n;
	for(int i=1;i<=n;i++)
	{
		if(tail-head>m)
		{
			head++;
				tail++;
		}
			cin>>a[i];
			for(int j=head,e=0;j<=tail;j++)
			{
				if(a[i]==a[j])
				{
					e=1;
					break;
				}
			}
			if(e!=1)
			{
				tail++;
				sum++;
			}
	}
	cout<<sum;
	return 0;
}