#include<bits/stdc++.h> 
using namespace std;
int m,n,a,sum[1005],x,y,ans;
int main(){
	scanf("%d%d",&m,&n);
	for(int i=1;i<=n;i++) sum[i] = -1;
	for(int i=1;i<=n;i++){
		scanf("%d",&a);
		for(int j=1;j<=m;j++){
			if(a == sum[j]) x=1;
			if(sum[j]!=-1) y++;
		}
		if(x==0){sum[y%m+1] = a;ans++;}
		x = 0, y = 0;
	}
	cout<<ans;
	return 0;
}