- HashSet
HashSet<Integer> hashSet = new HashSet<>(); for (int i : arr) { hashSet.add(i); }
import java.util.HashSet;
class Solution {
public int solution(int[] nums) {
HashSet<Integer> hashSet = new HashSet<>();
for (int i : nums) {
hashSet.add(i);
}
return hashSet.size()<nums.length/2 ? hashSet.size() : nums.length/2;
}
}