#include<iostream>
#include<algorithm>

using namespace std;

#define NMAX 100000

int main(){

	int N;
	int A[NMAX];
	int ans=0;

	cin>>N;

	for(int i=0;i<N;i++){
		cin>>A[i];
	}

	sort(A,A+N);

	for(int i=0;i<N;i++){
		if((i==0||A[i]!=A[i-1])&&(i==N-1||A[i]!=A[i+1])) ans++;
	}

	cout<<ans<<endl;

}