LeetCode之Distribute Candies

题目概述：

给一个偶数个数的整数数组，数组里相同的数代表同一种糖果，不同的数代表不同种类的糖果，把这些糖果平均分给弟弟和姐姐，返回姐姐可能得到的最多的糖果种类的个数。

思路：

如果糖果的种类数小于数组的一半，返回种类数，否则，返回数组的一半值。

示例：

Example 1:Input: candies = [1,1,2,2,3,3]Output: 3Explanation: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: 2Explanation: 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. 

代码：

class Solution {public:    int distributeCandies(vector<int>& candies) {        //candies呈升序排列        sort(candies.begin(),candies.end());        //candies数组的长度        int length=candies.size();        //candies的种类数        int num=1;        for(int i=1;i<length;i++)        {            if(candies[i]!=candies[i-1])            {                num++;            }        }        if(num>=length/2)            return length/2;        else            return num;    }};

另一种解法：

class Solution {public:    int distributeCandies(vector<int>& candies) {        unordered_set<int> kinds;        for (int kind : candies) {            kinds.insert(kind);        }        return min(kinds.size(), candies.size() / 2);    }};

set集合是无序集合容器。