#include <stdio.h>
#include <stdlib.h>
#define _CRT_SECURE_NO_WARNINGS 1

int asc(const void *a, const void *b) {
	return *(int *)a - *(int *)b;
}

int main(void) {

	int N = 0;
	int *edgh = NULL;
	int *p = NULL;
	int cnt = 0;
	int sinkisei = 0;

	scanf("%d", &N);

	edgh = (int *)malloc(N);

	//終端位置をNULLにする
	p = edgh + N;
	*p = -1;

	p = edgh;

	for (int i = 0; i < N; i++) {
		scanf("%d", p);
		p++;
	}

	//昇順にソートする
	qsort(edgh, N, sizeof(int), asc);

	p = edgh;

	while (*p != -1) {

		if (*p == *(p+1) ) {
			cnt++;
		}
		if (*p != *(p+1) && cnt == 0) {
			sinkisei += 1;
		}
		if (*p != *(p + 1) && cnt > 0) {
			cnt = 0;
		}
		p++;
	}
	printf("%d\n", sinkisei);

	free(edgh);
		 
	return 0;
}