# -*- coding: utf-8 -*-

"""

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].

"""

class Solution:

def arrayPairSum(self, nums):

"""

:type nums: List[int]

:rtype: int

>>> test1 = [1,4,3,2]

>>> s = Solution()

>>> s.arrayPairSum(test1)

4

"""

# 排序然后隔一取值

l = len(nums)

nums.sort()

sum_ = 0

if l == 2:

return min(nums)

for i in range(0, l, 2):

sum_ += nums[i]

return sum_

# return sum(sorted(nums)[::2])

if __name__ == '__main__':

import doctest

doctest.testmod(verbose=True)