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.

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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].

给定 2n 个整数的数组,将数组中元素分成 n 组,每组 2 个元素。求得这 n 组中每组元素的最小值之和m,使得m尽可能大。

实现

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import (
	"sort"
)

func (nums []int) int {
	sort.Ints(nums)
	sum := 0
	for i := 0; i < len(nums); i += 2 {
		sum += nums[i]
	}
	return sum
}

参考资料

• 561. Array Partition I