#include<iostream>
#include<algorithm>
using namespace std;
int a[100000];
int main(void){
  int n;

  cin>>n;
  if( n == 1 ){
    cout<<1<<endl;
    return 0;
  }
  for(int i = 0;i < n;i++ ){
    cin>>a[i];
  }
  sort( a, a+n);
  int cnt = 0;
  if( a[0] != a[1]) cnt++;
  if( a[n-2] != a[n-1] ) cnt++;
  for( int i = 1; i < n-1; i++){
    if( a[i] != a[i-1] &&
        a[i] != a[i+1] )cnt++;
  }
  cout<<cnt<<endl;
  return 0;

}