#include<bits/stdc++.h>
using namespace std;
int main()
{
	freopen("translate.in","r",stdin);
	freopen("translate.out","w",stdout);
	int x,y;
	cin>>x>>y;
	int a[1001];
	for(int i=1;i<=y;i++)
	    cin>>a[i];
	int b[1001]={0},c[1001]={0};
	int sum=0,earlyest=1;
	for(int i=1;i<=y;i++)
	{
		if(c[a[i]]==0)
		{
			if(b[0]!=x)
			{
				b[0]++;
				b[b[0]]=a[i];
				c[a[i]]=b[0];
			}
			else
			{
				if(earlyest>x)
				    earlyest=earlyest-x;
				c[b[earlyest]]=0;
				b[earlyest]=a[i];
				c[a[i]]=earlyest;
				earlyest++;
			}
			sum++;
		}
	}
	cout<<sum;
}