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 ofkinds 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.

題目大意：
給一個長度為偶數的整數數組，數組中不同數字都代表不同糖果，將糖果平均分給弟弟和妹妹，妹妹最多能得到幾種糖果。

思路：

• 記錄糖果種類，若糖果種類大於數組的一半，妹妹最多得到candies.size()/2種糖果,否則每種糖果都可以得到

int distributeCandies(vector<int>& candies) {
    int len=candies.size();
    sort(candies.begin(),candies.end());
    vector<int>::iterator iter1,iter2;
    iter1=unique(candies.begin(),candies.end());
    candies.erase(iter1,candies.end());
    int ans=0;
    //vector<int>::iterator iter1,iter2;
    for(iter2=candies.begin();iter2<candies.end();iter2++)
        ans++;
    return ans<=len/2?ans:len/2;
        
}

575. Distribute Candies