QUESTION:

Given an integer array with even length, where different numbers in this array represent different kinds of candies. Each number means one candy of the corresponding kind. You need to distribute these candies equally in number to brother and sister. Return the maximum number of kinds of candies the sister could gain.

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. 

Note:

1. The length of the given array is in range [2, 10,000], and will be even.
2. The number in given array is in range [-100,000, 100,000].

EXPLANATION:

就是平分给两个人，但是姐姐要拿到品种不同的个数。

分析如下：首先拿到姐姐可以获得多少个，再获取到一共有多少种蜡烛。

1.如果姐姐获取到的数量大于蜡烛种类，那么就算她每个拿一个，后面也必然有重复的，所以只能获取到蜡烛种类的种类。

2.如果姐姐获取到的输啦小于蜡烛种类，那么姐姐就只能获取到能够拿的数量。

SOLUTION:

public class Solution {
    public int distributeCandies(int[] candies) {
        int canGet = candies.length/2;
        Hashtable<Integer,Integer> candiesType = new Hashtable<>();
        for(int i = 0;i<candies.length;i++){
            int kind = candies[i];
            if(!candiesType.containsKey(kind))
                candiesType.put(kind,0);
            int value = candiesType.get(kind)+1;
            candiesType.put(kind,value);
        }
        int kind = candiesType.keySet().size();
        return canGet>kind?kind:canGet;
    }
}