#include <vector>
#include<algorithm>
using namespace std;

int solution(vector<int> nums)
{
    int answer = 0;
    
    int getCount = nums.size() / 2;

	sort(nums.begin(), nums.end());
	
	vector<int>::iterator iter_end = unique(nums.begin(), nums.end());

	nums.erase(iter_end, nums.end());


	if (nums.size() > getCount) {
		answer = getCount;
	}
	else if (nums.size() < getCount) {
		answer = nums.size();
	}
	else {
		answer = getCount;
	}
    
    return answer;
}