[문제링크 - 프로그래머스 - 포켓몬] https://school.programmers.co.kr/learn/courses/30/lessons/1845
import java.util.HashSet;
class Solution {
public int solution(int[] nums) {
HashSet<Integer> set = new HashSet<>();
for(int i=0; i<nums.length; i++){
set.add(nums[i]);
}
if(set.size() > nums.length/2)
return nums.length/2;
else
return set.size();
}
}