import java.util.*; public class Novelty2{ public static void main(String... args){ Scanner scan = new Scanner(System.in); int n = scan.nextInt(); System.out.println(counter(n,scan)); } public static int counter(int n,Scanner scan){ int[] list = new int[n]; for(int i = 0; i < n; i++){ list[i] = scan.nextInt(); } Arrays.sort(list); int count=0; int c=0; for(int i = 0; i < list.length-1; i++){ if(c>1)continue; if(list[i]==list[i+1])c++; if(list[i]!=list[i+1])c=1; if(c==1)count++; } return count; } }