Competitions

# Different-different

n integers are given. How many of them are different?

#### Input

The first line contains amount of numbers n (1n106). Second line contains n integers, each of them is no greater than 2 * 109 by absolute value.

#### Output

Print the amount of different numbers.

Time limit 3 seconds
Memory limit 128 MiB
Input example #1
1
3

Output example #1
1

Input example #2
5
9 15 22 15 22
Output example #2
3