Problem Statement

In a sequence of $N$ positive integers $a = (a_1, a_2, \\dots, a_N)$, how many different integers are there?

Constraints

• $1 \\leq N \\leq 1000$
• $1 \\leq a_i \\leq 10^9 \\, (1 \\leq i \\leq N)$
• All values in input are integers.

Input

Input is given from Standard Input in the following format:

$N$ $a_1$ $\\ldots$ $a_N$

Output

Print the answer.

Sample Input 1

6
1 4 1 2 2 1

Sample Output 1

3

There are three different integers: $1, 2, 4$.

Sample Input 2

1
1

Sample Output 2

1

Sample Input 3

11
3 1 4 1 5 9 2 6 5 3 5

Sample Output 3

7