#include <stdio.h>
#include <string.h>

int main(void) {
	// your code goes here
	int a;
	int *b;
	char data[100000];
	char *point;
	int count = 0;
	int i,j;
	
	scanf("%d\r\n", &a);
	fgets(data, sizeof(data), stdin);

	b = (int *)calloc(a, sizeof(int));
	point = strtok(data, " ");

	for (i=0; i<a; i++)
	{
		sscanf(point, "%d", b+i);

		for (j=0; j<i; j++)
		{
			if (*(b+i) == *(b+j))
			{
				break;
			}
		}
		
		if (j == i)
		{
			count++;
		}
		
		point = strtok(NULL, " ");
		if (point == NULL)
		{
			break;
		}
	}
	
	printf("%d\r", count);
	
	return 0;
}