#include<stdio.h>
#define same 1000000001

int main(void) {
	int N, count = 0;
	int A[10001];
	int check;
	scanf("%d", &N);
	for (int i = 0; i < N; i++) {
		scanf("%d", &A[i]);
	}
	for (int i = 0; i < N; i++) {
		if (A[i] == same) {
			continue;
		}
		check = 1;
		for (int j = i+1; j < N; j++) {
			if (A[i] == A[j]) {
				A[j] = same;
				check = 0;
			}
		}
		if (check) {
			count++;
		}
	}
	printf("%d", count);
}