#include <iostream>
using namespace std;
#include<deque>
#include<vector>
bool isInCache(int a,deque<int>d){
for(int i=0;i<d.size();i++){
if(a==d[i]){
return 1;
}
}
return 0;
}
int main() {
int M,N;
cin>>M>>N;
vector<int>v;
for(int i=0;i<N;i++){
int a;
cin>>a;
v.push_back(a);
}
int miss=0;
deque<int>d;
for(int i=0;i<v.size();i++){
if(isInCache(v[i],d)){
continue;
}
else if(!isInCache(v[i],d)){
miss++;
if(d.size()==M){
d.pop_front();
d.push_back(v[i]);
}
else{
d.push_back(v[i]);
}
}
}
cout<<miss;
}
// 64 位输出请用 printf("%lld")