Title

the problem link

Given an array of 2n integers, your task is to group these integers into n pairs of integer, say (a1, b1), (a2, b2), …, (an, bn) which makes sum of min(ai, bi) for all i from 1 to n as large as possible.

Example 1:
Input: [1,4,3,2]

Output: 4

Explanation: n is 2, and the maximum sum of pairs is 4 = min(1, 2) + min(3, 4).

Note: n is a positive integer, which is in the range of [1, 10000]. All the integers in the array will be in the range of [-10000, 10000].

题目大意:2n个元素的数组分成n个数对，让每个数对的min值和最大

Solution

//cpp:
class Solution {
public:
	int arrayPairSum(vector<int>& nums) {
		int ans = 0;
		sort(nums.begin(), nums.end(), less<int>());
		for (int i = 0; i < nums.size(); i += 2) {
			ans += nums[i];
		}
		return ans;
	}
};