#include <stdio.h>
#include<stdlib.h>

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

int main(void){
    int n;
    scanf( "%d", &n );
    int i, j, temp;
    long num[n + 2];
    int ans = 0;

    if( n == 1 ){
        ans = 1;
    }else{
    	num[0] = -1;
    	for( i = 0; i < n; i++ ){
    	    scanf( "%d", &num[i+1] );
    	}
    	num[n+1] = 100000000001;
    	qsort(num, n + 2, sizeof(long), compare_long);

        for( i = 1; i <= n; i++ ){
    		if( num[i] != num[i+1] && num[i] != num[i-1] ){
    			ans++;
    		}
        }
    }
    printf( "%d\n", ans );
}