575. Distribute Candies

其实就是问你数组里不同的元素能否超过二分之一。

不上描述了，上example吧

Example 1:
Input: candies = [1,1,2,2,3,3]
Output: 3
Explanation:
There are three different kinds of candies (1, 2 and 3), and two candies for each kind.
Optimal distribution: The sister has candies [1,2,3] and the brother has candies [1,2,3], too. 
The sister has three different kinds of candies. 
Example 2:
Input: candies = [1,1,2,3]
Output: 2
Explanation: For example, the sister has candies [2,3] and the brother has candies [1,1]. 
The sister has two different kinds of candies, the brother has only one kind of candies.

class Solution {
    public int distributeCandies(int[] candies) {
        HashSet set = new HashSet();
        for(int i = 0;i=candies.length/2)
            return candies.length/2;
        return set.size();
    }
}