Find unique numbers in array

Question

Well, I have to find how many different numbers are in an array.

For example if array is: 1 9 4 5 8 3 1 3 5

The output should be 6, because 1,9,4,5,8,3 are uniqu

Answer 1

A std::set contains only unique elements already.

#include 

int main()
{
    int a[] = { 1, 9, 4, 5, 8, 3, 1, 3, 5 };

    std::set sa(a, a + 9);
    std::cout << sa.size() << std::endl;
}