Problem Description

Rar the Cat likes collating numbers. Given a list of N integers, tell Rar the Cat how many unique integers there are in that list.

Input

The first line of input will contain one integer, N. The second line of input will contain N integers, containing the list of integers that Rar the Cat wants to collate.

Output

Your output should contain one integer, the number of unique integers there are in Rar the Cat's list.

Limits

Subtask 1 (33%): 1 ≤ N ≤ 1000000. The list of integers will fit into a 32-bit signed int.
Subtask 2 (67%): 1 ≤ N ≤ 1000000. The list of integers will NOT fit into a 64-bit unsigned int, but will be not more than 50 digits long.

Sample Input 1

10
1 2 3 4 5 6 6 8 9 10

Sample Output 1

9

Sample Input 2

10
-1 -2 -3 -4 0 0 -5 -6 -7 -1

Sample Output 2

8