#include<iostream>
#include<queue>
using namespace std;
const int maxn=1005;
int main(){
	queue<int>q;
	int m,n,x;
	int a[maxn]={};
	int ans=1;
	cin>>m>>n;
	cin>>x;
	a[x]=1;
	q.push(x);
	for(int i=2;i<=n;i++){
		cin>>x;
		if(!a[x]){
			if(q.size()<=m-1){
				q.push(x);
				a[x]=1;
				ans++;
			}else{
				q.pop();
				q.push(x);
				ans++;
			}
			
		}
	}
	cout<<ans;
	return 0;
	
}