407064: GYM102697 035 Distinct Numbers

You have a list of numbers. You want to figure out how many distinct (different) numbers are in the list. For example, the list [1, 2, 3, 4, 4, 5, 5] has 5 distinct numbers.

The first line of input contains a single positive integer $$$n$$$: the number of items in the list. The next line contains $$$n$$$ space-separated integers: the list.

Output a single positive integer $$$d$$$: the number of distinct numbers in the list.

5
2 2 3 5 6

4

4
1 2 3 4

4