#include <iostream>
#include <set>
using namespace std;
int main(){
    int N,K,A;
    while(cin>>N){
        set<int> s;
        for(int i=0;i<N;i++){
            cin>>A;
            s.insert(A);
        }
        int n=s.size();
        int r=N-n;
        cin>>K;
        if(K<=r)
            cout<<n<<endl;
        else
            cout<<n-(K-r)<<endl;
    }
    return 0;
}