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

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

int main(void)
{
    int N;
    int A[100000];
    int i, j;
    int count, s;

    scanf("%d", &N);
    for (i = 0; i < N; i++) {
        scanf("%d", &A[i]);
    }

    qsort(A, N, sizeof(int), asc);

    count = 0;
    for (i = 0; i < N; i++) {
        if ((i == 0) && (A[i] != A[i+1])) {
            count++;
        } else if ((i == (N-1)) && (A[i-1] != A[i])) {
            count++;
        } else if ((A[i-1] != A[i]) && (A[i] != A[i+1])) {
            count++;
        } else {
        }
    }

    printf("%d\n", count);

    return 0;
}