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+package leetcode.contains_duplicate;%0A%0Aimport java.util.HashSet;%0Aimport java.util.Set;%0A%0Apublic class Solution %7B%0A    public boolean containsDuplicate(int%5B%5D nums) %7B%0A        Set%3CInteger%3E set = new HashSet%3CInteger%3E();%0A        for(int x : nums)%7B%0A            set.add(x);%0A        %7D%0A        return set.size() != nums.length;%0A    %7D%0A%7D%0A

Add java solution for 217. Contains Duplicate