#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")