#include <bits/stdc++.h>
using namespace std;

signed main(){
  int N; cin >> N;
  map< int, int > freq;
  for( int i = 0; i < N; ++i ){
    int x; cin >> x;
    ++freq[ x ];
  }
  map< int, int > cnt;
  for( auto it = freq.begin(); it != freq.end(); ++it )
    ++cnt[ it->second ];
  cout << cnt[ 1 ] << endl;
  return 0;
}