Set

Given the sequence a_1, a_2, .., a_N.

How many values ​​are there in this sequence?

input

N
a_1 a_2 ... a_N

output

Output the number of types of values ​​in the sequence.

Constraint

• 1 \ leq N \ leq 10 ^ 5
• 1 \ leq a_i \ leq 10 ^ 9

Input example

6
8 6 9 1 2 1

Output example

Five

Example

Input

6
8 6 9 1 2 1

Output

5

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