Count the distinct values in an integer array.

Input

The first line contains n. The second line contains n integers.

$0 \le n \le 1000$ and $0 \le A_i \le 10^7$. When $n=0$, the array line may be empty.

Output

Print the number of distinct values.

Example

Input

5
1 1 2 3 4

Output

4